Open source runs the eval stack, but only its lower layers have settled
Two open harnesses carry most model benchmarking, Docker and OpenTelemetry won the plumbing, and larger companies bought most eval platforms in 2026.
- monthly Inspect AI downloads
- 2.9M
- benchmark adapters in Harbor
- 86
- eval-tool deals in 2026
- 7
- Dynatrace price for Arize
- $915M
- open licences changed after a deal
- 0
5 November 2026 · 12 min read · Dotted terms are in the glossary
On this page
Key findings
- Two harnesses carry most model benchmarking. UK AISI's Inspect AI draws 2.9 million PyPI downloads a month, and EleutherAI's lm-evaluation-harness 1.0 million (5 Nov 2026).[3][3] inspect-ai downloads pypistats Primary[7][7] lm-eval downloads pypistats Primary
- Harbor became the shared unit for agent benchmarks. Its 86 adapters cover SWE-bench, OSWorld, GAIA and HLE, and four other frameworks import its tasks.[33][33] Adapters folder Harbor Primary
- Academic harnesses age fast. Six well-known projects froze or retired since mid-2024, including HELM (maintenance mode since 1 June 2026) and the Open LLM Leaderboard (retired 13 March 2025).[39][39] HELM README Stanford CRFM Primary[44][44] End of the Open LLM Leaderboard Hugging Face Primary
- The app eval library is now a commodity. Every platform ships judges, datasets and a CI exit code. Only MLflow 3.18.0 (November 2026) ships a paired test between two runs.[86][86] Comparing evaluation runs MLflow Primary
- Eval and RL environments merged into one layer. OpenEnv (v0.12.0, 5 Nov 2026), verifiers and Harbor tasks now serve evaluation and training alike.[94][94] OpenEnv GitHub API Primary[109][109] verifiers Harbor docs Prime Intellect Primary
- OpenTelemetry won the transport, not the vocabulary. The OTel GenAI conventions still carry "Development" status, while OpenInference draws 8.6 million monthly downloads.[142][142] GenAI conventions overview OpenTelemetry Primary[138][138] OpenInference conventions downloads pypistats Primary
- Larger companies bought most eval platforms in 2026. ClickHouse bought Langfuse (16 Jan), OpenAI bought promptfoo (9 Mar) and Dynatrace closed Arize for $915M (1 Oct).[168][168] Langfuse acquisition ClickHouse Vendor[73][73] Joining OpenAI promptfoo Vendor[174][174] Dynatrace and Arize ITPro Secondary
- No acquirer changed an open licence. Most core projects stay MIT, Apache-2.0 or BSD. Phoenix's Elastic License and closed
ee/folders are the main traps for a hosted product.[88][88] LICENSE Arize Phoenix Primary[166][166] LICENSE Langfuse Primary - No result format has won. Inspect
.evallogs lead in practice, while the neutral Every Eval Ever schema drew 285 PyPI downloads last month.[149][149] Inspect eval logs docs UK AISI Primary[151][151] every-eval-ever downloads pypistats Primary
Only the bottom of the eval stack has settled
Every evaluation passes through the same seven layers, whatever the tool. The sandbox and the harness have settled. Grading, statistics and reporting have not.
Every evaluation follows the same path. A team writes tasks and runs them in a sandbox through a harness. Graders score each answer, statistics add error bars, traces keep the evidence, and reports show the result. Figure 1 shows each layer with its leading names and a status tag.
The Sandbox and the Harness Have Settled. Grading and Reporting Have Not.
The seven layers of an evaluation, bottom to top. A solid slab has one de facto choice; a broken slab has rival tools; the dashed slab is a standard still in draft.
- 7 · Reporting: Fragmented. Each source picks its own benchmarks and methods. Leaderboards; Dashboards (Langfuse 23.6M and MLflow 19.9M PyPI downloads a month, incl. SDK installs, 5 Nov 2026); Lab system cards
- 6 · Traces and storage: Draft. OpenTelemetry won the transport; the GenAI terms are still "Development". OTel GenAI conventions; OpenInference (8.6M downloads a month, 5 Nov 2026)
- 5 · Statistics: Fragmented. Each tool computes intervals in its own way. Confidence intervals; Item-response models; pass^k; Sequential tests
- 4 · Graders: Fragmented. Code checks, LLM judges, rubrics, reward models and human experts all compete. Tiles show judge libraries, sized by monthly PyPI downloads. autoevals (4.1M PyPI downloads a month, 5 Nov 2026); DeepEval (2.6M PyPI downloads a month, 5 Nov 2026); Ragas (1.1M PyPI downloads a month, 5 Nov 2026); openevals (1.0M PyPI downloads a month, 5 Nov 2026); agentevals (428k PyPI downloads a month, 5 Nov 2026); TruLens (20k PyPI downloads a month, 5 Nov 2026)
- 3 · Harness or runner: Standard. The de facto pair for model evals. Inspect AI (2.9M PyPI downloads a month, 5 Nov 2026); lm-evaluation-harness (1.0M PyPI downloads a month, 5 Nov 2026)
- 2 · Environments and sandboxes: Standard. Docker is the shared contract; cloud back ends swap freely. Docker; E2B · Modal · Daytona
- 1 · Tasks and datasets: Fragmented. Inspect tasks, lm-evaluation-harness YAML and Harbor folders compete. No task format has won. Harbor task folders (4.8M PyPI downloads a month (Harbor), 5 Nov 2026); lm-eval YAML (1.0M PyPI downloads a month (lm-evaluation-harness), 5 Nov 2026); Inspect tasks (867k PyPI downloads a month (inspect_evals), 5 Nov 2026); Hugging Face Datasets
Data table
| Layer | State | Tool or leader | Adoption | Date | Licence | Source |
|---|---|---|---|---|---|---|
| 7 · Reporting | Fragmented | Leaderboards (Epoch AI hub, Artificial Analysis, LMArena) | ||||
| 7 · Reporting | Fragmented | Dashboards | Langfuse 23.6M and MLflow 19.9M PyPI downloads a month, incl. SDK installs | 5 Nov 2026 | pypistats | |
| 7 · Reporting | Fragmented | Lab system cards (Each lab picks its own benchmarks) | ||||
| 6 · Traces and storage | Draft | OTel GenAI conventions (Status "Development") | OpenTelemetry docs | |||
| 6 · Traces and storage | Draft | OpenInference (Leads in practice) | 8.6M downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 5 · Statistics | Fragmented | Confidence intervals (Inspect) | ||||
| 5 · Statistics | Fragmented | Item-response models (Epoch AI) | ||||
| 5 · Statistics | Fragmented | pass^k (Success on all k tries) | ||||
| 5 · Statistics | Fragmented | Sequential tests (Stop early when the answer is clear) | ||||
| 4 · Graders | Fragmented | autoevals (Braintrust) | 4.1M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | DeepEval (Confident AI) | 2.6M PyPI downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 4 · Graders | Fragmented | Ragas (No commits since 24 Feb 2026) | 1.1M PyPI downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 4 · Graders | Fragmented | openevals (LangChain) | 1.0M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | agentevals (LangChain) | 428k PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | TruLens | 20k PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 3 · Harness or runner | Standard | Inspect AI (UK AISI) | 2.9M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 3 · Harness or runner | Standard | lm-evaluation-harness (EleutherAI) | 1.0M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 2 · Environments and sandboxes | Standard | Docker (Every major harness runs tasks in Docker containers) | ||||
| 2 · Environments and sandboxes | Standard | E2B · Modal · Daytona (Interchangeable cloud back ends) | ||||
| 1 · Tasks and datasets | Fragmented | Harbor task folders | 4.8M PyPI downloads a month (Harbor) | 5 Nov 2026 | Apache-2.0 | pypistats |
| 1 · Tasks and datasets | Fragmented | lm-eval YAML | 1.0M PyPI downloads a month (lm-evaluation-harness) | 5 Nov 2026 | MIT | pypistats |
| 1 · Tasks and datasets | Fragmented | Inspect tasks | 867k PyPI downloads a month (inspect_evals) | 5 Nov 2026 | MIT | pypistats |
| 1 · Tasks and datasets | Fragmented | Hugging Face Datasets (Shared dataset hub; no comparable count, so tiles in this layer are equal) |
The lower layers have settled. Docker containers, OpenAI-compatible APIs and the two main harnesses work almost everywhere. Cloud sandbox vendors such as E2B, Modal and Daytona now compete as interchangeable back ends.[155][155] Inspect sandboxing docs UK AISI Primary
The upper layers still change fast. Each tool grades, computes statistics, stores and reports in its own way. A different judge can change a ranking. The OpenTelemetry GenAI conventions still carry "Development" status.[142][142] GenAI conventions overview OpenTelemetry Primary
-
Layer De facto standard Open alternative Watch point Model benchmarks Inspect AI, lm-evaluation-harness lighteval, OpenCompass, NeMo Evaluator HELM in maintenance mode Agent benchmark tasks Harbor task format SWE-bench harness, OSWorld Docker cost at scale Environments for eval and RL OpenEnv step API, verifiers tau2-bench, AppWorld, BrowserGym Hub sizes unverified App and agent evals DeepEval (library), promptfoo (CLI) Giskard, openevals, LangWatch Scenario Ragas idle since February 2026 Self-hosted platform Langfuse, MLflow Opik, Agenta Phoenix under ELv2 Red team promptfoo garak, PyRIT, DeepTeam OpenAI owns promptfoo Tracing OpenTelemetry with OpenInference attributes OTel GenAI conventions GenAI conventions still "Development" Tool access MCP none Licence move to Apache-2.0 Sandboxes Docker images Kubernetes, Modal, Daytona, E2B Vendor lock-in at scale Result format Inspect .evallogsEvery Eval Ever Very low uptake Table 1. Layer-by-layer summary on 5 Nov 2026. How to read the download counts. Stars, licences and release dates come from the GitHub API on 5 Nov 2026. Monthly downloads come from the pypistats and npm APIs on the same day. Counts include CI and mirror traffic, so treat them as rough signals. SWE-bench, for example, shows 22.1 million PyPI downloads a month.[1][1] swebench downloads pypistats Primary
Two harnesses carry model benchmarking, and Harbor carries agent tasks
A model-benchmark harness runs a fixed set of tasks against a model and reports scores. Labs, safety institutes and researchers use them to compare models.
UK AISI's Inspect AI leads for agentic, sandboxed and safety evals. It draws 2.9 million PyPI downloads a month, almost three times the count for lm-evaluation-harness.[3][3] inspect-ai downloads pypistats Primary[7][7] lm-eval downloads pypistats Primary Its README lists over 200 ready-made evaluations.[21][21] Inspect AI README UK AISI Primary Each evaluation combines a dataset, solvers and scorers, and MCP tools plug in directly.[22][22] Inspect docs folder UK AISI Primary
Inspect has become a de facto verification standard. Epoch AI's Benchmarking Hub runs on Inspect and shows each question in the Inspect viewer.[27][27] Benchmarking Hub update Epoch AI Primary Hugging Face marks a score as verified only after an Inspect run in HF Jobs.[28][28] Eval Results Hugging Face Hub docs Primary Groq's openbench runs over 95 benchmarks on it.[25][25] openbench README Groq Primary
EleutherAI's lm-evaluation-harness stays the standard for open weights. It defines each task as a YAML file and supports vLLM, SGLang, llama.cpp and OpenAI-compatible APIs.[30][30] lm-evaluation-harness README EleutherAI Primary It also powered the Hugging Face Open LLM Leaderboard.
Harbor became the shared unit for agent benchmarks. A Harbor task is a small folder with an instruction, a Dockerfile and a test script.[32][32] create-task skill Harbor Primary Its 86 adapters include SWE-bench, OSWorld, GAIA and HLE.[33][33] Adapters folder Harbor Primary Inspect, verifiers, OpenEnv and NeMo Evaluator all import Harbor tasks. Harbor is the official harness for Terminal-Bench 2.0.[31][31] Harbor README Primary
The Most-Starred Harnesses Are Not the Most Used
Each dot is a harness: GitHub stars (across) against monthly PyPI downloads (up, log scale), 5 November 2026.
- Very active or active
- Maintenance mode
Data table
| Point | GitHub stars | Monthly PyPI downloads (thousands) | Category | Note |
|---|---|---|---|---|
| Harbor | 6821 | 4,800k | Very active or active | 4.8M a month |
| Inspect AI | 3185 | 2,900k | Very active or active | 2.9M a month with 3,185 stars |
| lm-evaluation-harness | 14408 | 1,000k | Very active or active | Most stars, 1.0M a month |
| inspect_evals | 733 | 867k | Very active or active | |
| SWE-bench | 6149 | 22,100k | Very active or active | Mostly CI traffic |
| lighteval | 2579 | 6k | Very active or active | Likely a data gap |
| OpenCompass | 7563 | 3k | Very active or active | |
| openbench | 831 | 2k | Very active or active | |
| HELM | 2964 | 1k | Maintenance mode | Maintenance since 1 Jun 2026 |
Inspect also ships the strongest statistics of any harness. It offers standard errors, bootstrap errors, Wilson intervals, clustered errors and Krippendorff's alpha for judge agreement.[29][29] Inspect metrics docs UK AISI Primary
Academic leaderboard harnesses age fast. Six well-known projects froze or retired since mid-2024. Stanford's HELM entered maintenance mode on 1 June 2026.[39][39] HELM README Stanford CRFM Primary OpenAI stopped updating simple-evals in July 2025.[41][41] simple-evals README OpenAI Primary Hugging Face retired the Open LLM Leaderboard on 13 March 2025.[44][44] End of the Open LLM Leaderboard Hugging Face Primary
Well-Known Eval Projects Freeze Every Few Months
Projects that froze, retired or went idle, July 2024 to November 2026.
What to notice
- Five of the eight events fall in 2026.
Data table
| Date | Lane | Event | Kind | Note |
|---|---|---|---|---|
| 2024-07 | Harnesses and leaderboards | BIG-bench last push; repo archived | shutdown | |
| 2025-03-13 | Harnesses and leaderboards | Open LLM Leaderboard retired | shutdown | Results stay as datasets; Eval Results replaces it |
| 2025-07 | Harnesses and leaderboards | simple-evals frozen | shutdown | Still hosts HealthBench, BrowseComp, SimpleQA code |
| 2026-02-24 | App and platform tools | Ragas last commit | other | Treat as unmaintained |
| 2026-03-03 | App and platform tools | Helicone hosted product in maintenance | shutdown | After Mintlify deal |
| 2026-04 | Harnesses and leaderboards | Lakera PINT benchmark archived | shutdown | |
| 2026-06-01 | Harnesses and leaderboards | HELM enters maintenance mode | shutdown | |
| 2026-10-16 | App and platform tools | langsmith-sdk monorepo archived | other | SDKs moved to two new repos |
-
Project Maintainer Licence Stars Monthly downloads Status Best for Inspect AI[2][2] Inspect AI GitHub Primary UK AISI, with Meridian Labs MIT 3,185 2.9M[3][3] inspect-ai downloads pypistats Primary Very active Agentic, sandboxed and safety evals inspect_evals[4][4] inspect_evals GitHub Primary Generality Labs, with UK AISI MIT 733 867k[5][5] inspect-evals downloads pypistats Primary Very active Ready-made evals for Inspect lm-evaluation-harness[6][6] lm-evaluation-harness GitHub Primary EleutherAI MIT 14,408 1.0M[7][7] lm-eval downloads pypistats Primary Very active Open-weights and log-likelihood benchmarks Harbor[8][8] Harbor GitHub API Primary Harbor Framework team (Terminal-Bench) Apache-2.0 6,821 4.8M[9][9] harbor downloads pypistats Primary Very active Containerised agent benchmarks SWE-bench[10][10] SWE-bench GitHub Primary SWE-bench team (Princeton, Stanford) MIT 6,149 22.1M (CI-heavy)[1][1] swebench downloads pypistats Primary Active Coding-agent benchmark OpenCompass[11][11] OpenCompass GitHub Primary Shanghai AI Lab Apache-2.0 7,563 3k Active Chinese and multimodal benchmarks lighteval[12][12] lighteval GitHub Primary Hugging Face MIT 2,579 6k (likely a data gap)[13][13] lighteval downloads pypistats Primary Active, no release in 2026 Hugging Face models and tasks NeMo Evaluator[14][14] NeMo Evaluator GitHub Primary NVIDIA Apache-2.0 359 n/a Active Benchmarks with interceptors openbench[15][15] openbench GitHub Primary Groq MIT 831 2k Active Provider benchmarks on Inspect HELM[16][16] HELM GitHub Primary Stanford CRFM Apache-2.0 2,964 1k Maintenance since 1 Jun 2026 Historical comparisons OpenAI Evals[17][17] OpenAI Evals GitHub Primary OpenAI MIT 19,709 n/a Dormant Old eval registry simple-evals[18][18] simple-evals GitHub Primary OpenAI MIT 4,695 n/a Frozen since Jul 2025 Reference code for HealthBench, BrowseComp, SimpleQA BIG-bench[19][19] BIG-bench GitHub Primary Google Apache-2.0 3,245 n/a Archived Historical tasks HAL harness[20][20] HAL harness GitHub Primary Princeton PLI none stated 308 n/a Archived Historical agent leaderboard Table 2. GitHub API and pypistats, 5 Nov 2026. The Inspect ecosystem. Meridian Labs builds the web UI and add-ons for transcript analysis, workflows at scale, Harbor tasks, monitors and cloud sandboxes.[23][23] Meridian Labs repos GitHub search Primary Generality Labs, a London nonprofit, maintains inspect_evals and now accepts pull requests only from approved contributors.[24][24] inspect_evals README Primary NVIDIA's NeMo Evaluator exports Inspect logs.[26][26] NeMo Evaluator README NVIDIA Primary Solvers can be ReAct agents, custom agents, multi-agent setups or a human. An "agent bridge" lets Inspect run outside agents.[22][22] Inspect docs folder UK AISI Primary
lm-evaluation-harness details. A plugin system from September 2026 lets teams add backends, filters and metrics from their own packages.[30][30] lm-evaluation-harness README EleutherAI Primary Backends also include Hugging Face, NeMo and Megatron-LM. The Hugging Face backend stays the reference, and a script checks vLLM results against it. The README claims use in hundreds of papers and names NVIDIA, Cohere, BigCode, Nous Research and Mosaic ML.
Harbor and SWE-bench details. Harbor evaluates any agent, such as Claude Code, OpenHands or Codex CLI, and runs thousands of environments in parallel on cloud sandboxes. It also generates RL rollouts.[31][31] Harbor README Primary Terminal-Bench 1 now sends new users to Harbor.[34][34] Terminal-Bench 1 README Primary SWE-bench runs tasks in Docker and on Modal. It released SWE-bench Multimodal v2, with 480 tasks, on 1 September 2026.[35][35] SWE-bench README Primary
Other active harnesses. lighteval claims over 1,000 tasks, but its last tagged release dates from November 2025.[36][36] lighteval README Hugging Face Primary OpenCompass added the OpenAI Responses API and a LiteLLM gateway in July 2026. In September 2026 it released AgentCompass, which separates models, benchmarks, harnesses and environments.[37][37] OpenCompass README Primary NeMo Evaluator adds an interceptor proxy, confidence intervals and Harbor agents.[26][26] NeMo Evaluator README NVIDIA Primary Epoch AI fits a Bayesian item-response model in its Capabilities Index package.[38][38] Capabilities Index package Epoch AI Primary
Frozen and retired, in detail. HELM publishes a policy page on what maintenance mode covers.[40][40] Maintenance mode policy HELM Primary The OpenAI Evals README sends users to the OpenAI Dashboard; recent commits only pin CI dependencies.[42][42] Evals README OpenAI Primary Princeton archived the HAL harness, and the team now works on agent reliability.[43][43] HAL harness README Princeton PLI Primary Open LLM Leaderboard results stay available as datasets.[45][45] Leaderboards docs Hugging Face Primary Its successor, Eval Results, stores scores in each model repo and feeds per-benchmark boards.[28][28] Eval Results Hugging Face Hub docs Primary
The app eval library became a commodity; platforms now compete on traces and simulation
These tools test a team's own application or agent, not a bare model. Code-first libraries run tests in a script or in CI. Platforms add trace storage, dashboards, datasets and human review.
Every tool now ships the same core. All of them offer LLM judges, datasets, experiments and a pass-or-fail exit code for CI.[92][92] CI/CD docs promptfoo Primary[93][93] Experiments in CI/CD Langfuse Primary Most gates compare a pass rate with a fixed threshold. Few tools say with statistical confidence whether a change made the agent worse.
Only MLflow ships a paired test. Version 3.18.0, from early November 2026, compares two runs with McNemar or Wilcoxon tests and a bootstrap interval.[86][86] Comparing evaluation runs MLflow Primary No other platform ships a paired test today.
Download counts favour platforms with production SDKs. Langfuse draws 23.6 million PyPI downloads a month, and MLflow 19.9 million.[59][59] langfuse downloads pypistats Primary[61][61] mlflow downloads pypistats Primary Both counts include SDK installs in production apps, so they overstate pure eval use. Among code-first libraries, autoevals and DeepEval lead.[55][55] autoevals downloads pypistats Primary[49][49] deepeval downloads pypistats Primary
Two Platforms With Production SDKs Dwarf the Eval Libraries
Monthly PyPI downloads, in millions, on 5 November 2026. promptfoo is an npm package and is shown with its npm count.
- Trace-and-eval platform
- Code-first library
- npm package
Data table
| Item | Value | Category |
|---|---|---|
| Langfuse (ClickHouse · MIT + closed ee/) | 23.6M | Trace-and-eval platform |
| MLflow (Databricks-led · Apache-2.0) | 19.9M | Trace-and-eval platform |
| autoevals (Braintrust · MIT) | 4.1M | Code-first library |
| promptfoo (npm) (OpenAI · MIT) | 3.6M | npm package |
| DeepEval (Confident AI · Apache-2.0) | 2.6M | Code-first library |
| Opik (Comet · Apache-2.0) | 1.7M | Trace-and-eval platform |
| Ragas (VibrantLabs · Apache-2.0) | 1.1M | Code-first library |
| openevals (LangChain · MIT) | 1.0M | Code-first library |
| Evidently (Evidently AI · Apache-2.0) | 823k | Trace-and-eval platform |
| W&B Weave (CoreWeave · Apache-2.0 SDK) | 817k | Trace-and-eval platform |
| Arize Phoenix (Dynatrace · Elastic-2.0) | 626k | Trace-and-eval platform |
| agentevals (LangChain · MIT) | 428k | Code-first library |
| LangWatch Scenario (LangWatch · Apache-2.0) | 128k | Code-first library |
| TruLens (TruEra · MIT) | 20k | Code-first library |
| Giskard v3 (Giskard · Apache-2.0) | 13k | Code-first library |
| Agenta (Agenta · MIT + closed ee/) | 13k | Trace-and-eval platform |
Platforms now compete on three things. They compete on trace storage at scale, on simulated users and on scoring agent trajectories. DeepEval ships a conversation simulator, and LangWatch Scenario tests agents against a simulated user and a judge.[83][83] Scenario README LangWatch Primary LangChain's agentevals scores trajectories with strict, unordered, subset and superset match modes.[79][79] agentevals README LangChain Primary
Every Tool Gates CI, but Only MLflow Runs a Paired Test
Features that the leading app and agent eval tools document, November 2026. Full = documented; Partial = limited; None = not offered; n/a = not stated in our sources.
| Tool | CI pass/fail gate | OpenTelemetry traces ingest or export | Simulated users | Trajectory checks | Paired test vs baseline |
|---|---|---|---|---|---|
| promptfoo OpenAI · MIT | Documented GitHub Action before/after | Documented OTLP receiver | Not stated in our sources | Documented checks against traces | Not offered |
| CI pass/fail gate: GitHub Action before/afterOpenTelemetry traces: OTLP receiverTrajectory checks: checks against traces | |||||
| DeepEval Confident AI · Apache-2.0 | Documented deepeval test run | Documented exporter | Documented conversation simulator | Limited tool correctness, plan adherence | Not offered |
| CI pass/fail gate: deepeval test runOpenTelemetry traces: exporterSimulated users: conversation simulatorTrajectory checks: tool correctness, plan adherence | |||||
| Langfuse ClickHouse · MIT + ee/ | Documented | Documented OTel endpoint | Not stated in our sources | Not stated in our sources | Not offered |
| OpenTelemetry traces: OTel endpoint | |||||
| MLflow Databricks-led · Apache-2.0 | Documented | Documented | Not stated in our sources | Not stated in our sources | Documented McNemar / Wilcoxon + bootstrap |
| Paired test vs baseline: McNemar / Wilcoxon + bootstrap | |||||
| Arize Phoenix Dynatrace · ELv2 | Documented | Documented OpenInference | Not stated in our sources | Not stated in our sources | Not offered |
| OpenTelemetry traces: OpenInference | |||||
| TruLens TruEra · MIT | Documented | Documented | Not stated in our sources | Not stated in our sources | Not offered |
| LangWatch Scenario LangWatch · Apache-2.0 | Documented | Not stated in our sources | Documented simulated user + judge | Not stated in our sources | Not offered |
| Simulated users: simulated user + judge | |||||
| agentevals LangChain · MIT | Documented | Not stated in our sources | Not stated in our sources | Documented 4 match modes | Not offered |
| Trajectory checks: 4 match modes | |||||
What to notice
- Read the shaded column: only MLflow has a full mark.
Three gaps stay common. Few tools test a pure black-box agent without code. Few ship stateful copies of business tools. Only MLflow runs a paired test between a candidate and a baseline.
Some popular libraries have slowed. Ragas made RAG metrics such as faithfulness popular, but its last commit dates from 24 February 2026.[76][76] Ragas commits GitHub Primary Giskard rewrote its library as v3 for multi-turn agents and no longer maintains v2.[77][77] OSS README Giskard Primary LangChain archived its langsmith-sdk monorepo on 16 October 2026; the platform stays closed.[69][69] langsmith-sdk GitHub Primary
-
Project Maintainer Licence Stars Monthly downloads Status Best for promptfoo[46][46] promptfoo GitHub Primary OpenAI (acquired 2026, deal closed) MIT 26,875 npm 3.6M[47][47] promptfoo downloads npm Primary Very active YAML evals, CI gates, red team DeepEval[48][48] DeepEval GitHub Primary Confident AI Apache-2.0 19,318 2.6M[49][49] deepeval downloads pypistats Primary Very active Pytest-style tests in Python Ragas[50][50] Ragas GitHub Primary VibrantLabs Apache-2.0 16,247 1.1M Idle since 24 Feb 2026 RAG metrics Giskard v3[51][51] Giskard GitHub Primary Giskard (Paris) Apache-2.0 5,945 13k Active, new rewrite Multi-turn agent checks and scans openevals[52][52] openevals GitHub Primary LangChain MIT 1,244 1.0M Active Ready-made LLM judges agentevals[53][53] agentevals GitHub Primary LangChain MIT 757 428k Slowing Trajectory scoring autoevals[54][54] autoevals GitHub Primary Braintrust MIT 1,072 4.1M, npm 2.3M[55][55] autoevals downloads pypistats Primary Active Scorer library in Python and TS TruLens[56][56] TruLens GitHub Primary TruEra, with Snowflake ties MIT 3,628 20k Active Feedback functions, RAG triad LangWatch Scenario[57][57] LangWatch Scenario GitHub Primary LangWatch (Amsterdam) Apache-2.0 1,015 128k Active Simulated users against agents Langfuse[58][58] Langfuse GitHub Primary ClickHouse (acquired Jan 2026) MIT, plus closed ee/37,058 23.6M, npm 7.7M[59][59] langfuse downloads pypistats Primary Very active Self-hosted traces and evals MLflow[60][60] MLflow GitHub Primary Databricks-led open project Apache-2.0 28,693 19.9M[61][61] mlflow downloads pypistats Primary Very active Evals inside an ML platform Opik[62][62] Opik GitHub Primary Comet Apache-2.0 23,200 1.7M[63][63] opik downloads pypistats Primary Very active Self-hosted platform, fully open Arize Phoenix[64][64] Arize Phoenix GitHub Primary Dynatrace (acquired Oct 2026) Elastic-2.0 12,161 626k Very active Tracing and evals, not for resale as a service W&B Weave[65][65] W&B Weave GitHub Primary CoreWeave Apache-2.0 (SDK only) 1,145 817k Active Teams already on W&B Evidently[66][66] Evidently GitHub Primary Evidently AI Apache-2.0 8,042 823k Slowing ML and LLM monitoring reports Agenta[67][67] Agenta GitHub Primary Agenta (Berlin) MIT, plus closed ee/4,887 13k Very active Prompt playground and evals Kiln[68][68] Kiln GitHub Primary Kiln MIT library, source-available app 5,255 n/a Active Desktop eval and fine-tune app LangSmith SDK[69][69] langsmith-sdk GitHub Primary LangChain MIT (platform closed) 1,083 (old repo) n/a Old repo archived 16 Oct 2026 Teams on LangSmith Table 3. GitHub API, pypistats and npm, 5 Nov 2026. Code-first libraries.
- promptfoo puts evals in YAML files with providers, prompts, tests and assertions. It calls any HTTP, WebSocket or MCP endpoint.[70][70] HTTP provider docs promptfoo Primary It receives OpenTelemetry traces and checks agent trajectories against them.[71][71] Tracing docs promptfoo Primary A GitHub Action runs a before-and-after comparison on each pull request.[72][72] GitHub Action docs promptfoo Primary The company claims 350,000 developers and teams at over a quarter of the Fortune 500 (vendor claim).[73][73] Joining OpenAI promptfoo Vendor Release 0.125.1 shipped on 25 October 2026.
- DeepEval writes tests as pytest-style
LLMTestCaseobjects. Its metrics include G-Eval, task completion, tool correctness and plan adherence.deepeval test rungates CI.[75][75] CI/CD docs DeepEval Primary - Giskard v3 splits into
giskard-checks,giskard-scanandgiskard-agents.[77][77] OSS README Giskard Primary - openevals builds judges with one
create_llm_as_judgecall.[78][78] openevals README LangChain Primary autoevals offers LLM, heuristic, embedding and RAG scorers in Python and TypeScript.[80][80] autoevals repo Braintrust Primary Braintrust keeps its platform closed and raised an $80M Series B in February 2026 (secondary source).[81][81] Braintrust Series B SiliconANGLE Secondary - TruLens traces apps with OpenTelemetry, scores them with "feedback functions" and ships a Snowflake Cortex provider.[82][82] TruLens README Primary
- LangWatch Scenario combines a description, the agents and a script of turns and checks. It calls the agent through its public interface and mocks tools, databases and APIs for offline runs.[83][83] Scenario README LangWatch Primary
Trace-and-eval platforms.
- Langfuse stores traces, sessions, datasets, experiments, judge scores and human annotation queues. It versions a dataset on every change. Self-hosting runs on PostgreSQL, Redis, ClickHouse and S3.[84][84] Self-hosting docs Langfuse Primary It accepts OpenTelemetry traces directly.[85][85] llms.txt Langfuse Primary
- MLflow adds
mlflow.genai.evaluate()with scorers, judges and tracing.[86][86] Comparing evaluation runs MLflow Primary - Opik runs on ClickHouse, MySQL, Redis and MinIO with a Helm chart, and keeps its whole code base under Apache-2.0.[87][87] Self-host architecture Opik Primary
- Arize Phoenix traces with OpenInference. The server and
phoenix-evalsuse the Elastic License 2.0; the client and OpenTelemetry packages use Apache-2.0.[88][88] LICENSE Arize Phoenix Primary - W&B Weave traces functions with
@weave.op. The repo holds only the SDK and server bindings. Self-managed Weave runs inside W&B Self-Managed with ClickHouse, and CoreWeave hosts the docs.[89][89] Weave self-managed docs CoreWeave Primary - Evidently offers over 100 metrics, test suites and reports; its last push dates from late September 2026.[66][66] Evidently GitHub Primary Agenta combines a prompt playground, evaluation and observability.[90][90] LICENSE Agenta Primary Kiln keeps its core library MIT, but its desktop app uses a fair-code licence.[91][91] Kiln README Primary
Eval environments and RL training environments merged into one layer
An environment gives an agent a world to act in. It holds tools, data and rules, and it scores what the agent does. In 2026 the same environment often serves for evaluation and for RL training.
OpenEnv offers one step API for any environment. It exposes reset(), step() and state() over a WebSocket, and each environment is a Docker image.[106][106] OpenEnv README Primary A twelve-member technical committee now governs it, including Meta-PyTorch, Hugging Face, Nvidia, Microsoft and Modal. Version 0.12.0 shipped on 5 November 2026.[94][94] OpenEnv GitHub API Primary
verifiers links environments to training. Prime Intellect's library defines tasksets, harnesses and agents, and each rollout produces a trace.[108][108] verifiers overview Prime Intellect Primary A HarborTaskset loads Harbor tasks such as Terminal-Bench 2.[109][109] verifiers Harbor docs Prime Intellect Primary The library draws 762,000 PyPI downloads a month.[97][97] verifiers downloads pypistats Primary
The pieces mostly cooperate. Harbor defines tasks and sandboxes, and OpenEnv defines the step API and hosting. verifiers adds rubrics and training links, and Inspect adds logging and scoring. The story below follows one task through both uses.
One Agent Task Now Serves as a Test and as Training Data
How a single Harbor task flows through the shared open stack in 2026.
Step 1
Write the task
A Harbor folder: instruction.md, task.toml, environment/Dockerfile, optional solution, tests/test.sh.
ExampleA Terminal-Bench 2 task
Step 1 of 7: One stage: a task folder.
reset(). The same image runs locally, on a cloud sandbox or as a Hugging Face Space.[106][106] OpenEnv README PrimaryFour Open Projects Join Evaluation and Training
Each project owns one part of the shared layer, and each imports the others.
Tasks and sandboxes
Harbor
86 benchmark adapters
- Apache-2.0 · 6,821 stars
- 4.8M monthly PyPI downloads
- Official harness for Terminal-Bench 2.0
Step API and hosting
OpenEnv
40+ ready-made environments
- BSD-3-Clause · 2,833 stars
- 12-member technical committee
- v0.12.0 on 5 Nov 2026
Rubrics and training
verifiers
762k monthly PyPI downloads
- MIT · 4,768 stars
- Loads Harbor tasks
- 400+ Hub environments claimed (Oct 2025, unverified)
Logging and scoring
Inspect AI
200+ ready-made evaluations
- MIT · 3,185 stars
- OpenEnv evaluates with Inspect
- Petri now runs natively on Inspect
Simulated users are maturing in two places. Sierra's tau2-bench v2.0 tests customer-service agents in six languages and full-duplex voice. Its text and voice sets hold 900 tasks each.[111][111] tau2-bench README Sierra Primary Meridian Labs' Petri runs an auditing agent against a target model and scores transcripts with a rubric.[117][117] Petri README Meridian Labs Primary
-
Project Maintainer Licence Stars Monthly downloads Status Best for OpenEnv[94][94] OpenEnv GitHub API Primary OpenEnv technical committee (Meta-PyTorch, Hugging Face and others) BSD-3-Clause 2,833 49k[95][95] openenv downloads pypistats Primary Very active, v0.12.0 on 5 Nov 2026 One step API for any environment verifiers[96][96] verifiers GitHub Primary Prime Intellect MIT 4,768 762k[97][97] verifiers downloads pypistats Primary Very active RL and eval environments, Environments Hub community-environments[98][98] community-environments GitHub Primary Prime Intellect Apache-2.0 264 n/a Active Shared environment library tau2-bench[99][99] tau2-bench GitHub Primary Sierra MIT 2,403 n/a Very active, v2.0.0 in Oct 2026 Customer-service agents, text and voice AppWorld[100][100] AppWorld GitHub Primary Stony Brook NLP Apache-2.0 548 662k (CI-heavy)[101][101] appworld downloads pypistats Primary Active Apps, APIs and coding agents BrowserGym[102][102] BrowserGym GitHub Primary ServiceNow Research Apache-2.0 1,427 14k Active Web agents AgentLab[103][103] AgentLab GitHub Primary ServiceNow Research Apache-2.0 661 n/a Active Large parallel web-agent runs OSWorld[104][104] OSWorld GitHub Primary XLANG Lab (HKU) Apache-2.0 3,251 n/a Active, no release since 2024 Desktop computer-use agents Petri[105][105] inspect_petri GitHub API Primary Meridian Labs MIT 1,402 48k Very active Alignment audits with an auditor agent Table 4. GitHub API and pypistats, 5 Nov 2026. - OpenEnv. Farama's Gymnasium inspired the design. A Harbor integration runs Claude Code, Codex and other agents on Harbor tasks. OpenEnv scores with rubrics and evaluates with Inspect AI. The repo moved from
meta-pytorchto its ownopenenvorganisation. Committee members also include Prime Intellect and Unsloth.[106][106] OpenEnv README Primary - verifiers. A harness is the program that runs the model; an agent combines a harness, a model and a runtime policy. Toolsets install as MCP servers.[108][108] verifiers overview Prime Intellect Primary It links to the Environments Hub, prime-rl and hosted training.[107][107] verifiers README Prime Intellect Primary
- tau2-bench. Covers airline, retail and telecom. A live leaderboard runs at taubench.com. Harbor ships a
tau3-benchadapter, but no separate tau3 repo exists yet.[111][111] tau2-bench README Sierra Primary - AppWorld. A controllable world of apps and people for function-calling and coding agents; ACL 2024 best resource paper.[112][112] AppWorld README Stony Brook NLP Primary
- BrowserGym and AgentLab. BrowserGym bundles MiniWoB, WebArena, VisualWebArena, WorkArena and AssistantBench.[113][113] BrowserGym README ServiceNow Primary AgentLab runs large parallel experiments on it with Ray.[114][114] AgentLab README ServiceNow Primary Both repos warn that they are research tools, not consumer products.
- OSWorld. Runs desktop agents in VMs on VMware, VirtualBox, Docker, AWS or Azure. OSWorld-Verified fixed community-reported issues in July 2025. The last tagged release dates from June 2024.[115][115] OSWorld README XLANG Lab Primary
- ControlArena. UK AISI and Redwood Research built it for AI control experiments, where a red-team model tries to beat safety measures. MIT-licensed, 15 settings.[116][116] ControlArena repository Primary
- Petri. Generates scenarios from seed instructions and simulates tools. It moved from Anthropic's safety-research organisation to Meridian Labs.[117][117] Petri README Meridian Labs Primary
- OpenEnv. Farama's Gymnasium inspired the design. A Harbor integration runs Claude Code, Codex and other agents on Harbor tasks. OpenEnv scores with rubrics and evaluates with Inspect AI. The repo moved from
Four open red-team tools lead, and their owners now matter as much as their features
Red-team tools attack a model or an agent on purpose. They look for jailbreaks, prompt injection, data leaks and unsafe tool use.
promptfoo has the widest plugin set and the most users. It holds 72 red-team plugin docs, including excessive agency, MCP attacks and memory poisoning.[124][124] Red-team plugins folder promptfoo Primary Domain packs cover insurance, finance and medicine. By default it generates attacks through a remote service, and its docs rate local generation quality as generally low.[125][125] Red-team configuration promptfoo Primary
garak and PyRIT suit code-driven testing. NVIDIA's garak combines probes, detectors and harnesses, and a REST generator connects it to any endpoint.[126][126] garak README NVIDIA Primary Microsoft's PyRIT composes single-turn, multi-turn and compound attacks in Python, over HTTP, WebSockets or Playwright.[128][128] PyRIT README Microsoft Primary DeepTeam lists over 50 vulnerabilities and scores them locally with LLM judges.[129][129] DeepTeam README Confident AI Primary
promptfoo Dwarfs the Other Open Red-Team Tools in Downloads
Monthly downloads on 5 November 2026. Square area is proportional to downloads.
Area is proportional to monthly downloads
Data table
| Item | Value | Note |
|---|---|---|
| promptfoo | 3.6M | OpenAI · MIT · npm, whole package |
| PyRIT | 72k | Microsoft · MIT |
| DeepTeam | 71k | Confident AI · Apache-2.0 |
| garak | 39k | NVIDIA · Apache-2.0 |
Owners now shape the choice. OpenAI owns promptfoo, which may worry buyers who test competing models. Microsoft and NVIDIA back PyRIT and garak, so these two make the safest long-term bets for neutrality.
-
Project Maintainer Licence Stars Monthly downloads Status Best for promptfoo redteam[46][46] promptfoo GitHub Primary OpenAI MIT 26,875 npm 3.6M (whole package) Very active Widest plugin set, CI use garak[118][118] garak GitHub Primary NVIDIA Apache-2.0 9,872 39k[119][119] garak downloads pypistats Primary Very active Scanner for any REST endpoint PyRIT[120][120] PyRIT GitHub Primary Microsoft MIT 4,755 72k[121][121] pyrit downloads pypistats Primary Very active Multi-turn attacks composed in code DeepTeam[122][122] DeepTeam GitHub Primary Confident AI Apache-2.0 3,085 71k[123][123] deepteam downloads pypistats Primary Active, last release Nov 2025 Red team on top of DeepEval Table 5. GitHub API, pypistats and npm, 5 Nov 2026. Neighbouring tools.
- Giskard's
giskard-scancovers injection, jailbreaks and harmful content.[77][77] OSS README Giskard Primary - AgentDojo from ETH Zurich measures indirect prompt injection with code-based checks.[130][130] AgentDojo GitHub Primary
- Snyk's agent-scan checks local agent configs and MCP servers, but needs a Snyk token.[131][131] agent-scan README Snyk Primary
- Lakera archived its PINT benchmark in April 2026.[132][132] PINT benchmark GitHub Primary
- Singapore's Project Moonshot, an Apache-2.0 toolkit, remains in beta at version 0.7.6.[133][133] Project Moonshot repository Primary
- OWASP's AI Testing Guide v1 gives a free test method for AI systems.[134][134] OWASP AI Testing Guide Primary OWASP's Top 10 for Agentic Applications names risks such as agent goal hijack and tool misuse.[135][135] Top 10 for Agentic Applications for 2026 OWASP Primary
- Giskard's
OpenTelemetry won the transport, but the vocabulary and result formats remain open
OpenTelemetry carries traces in almost every eval platform. On top of it, attribute vocabularies, result formats and tool protocols are at different stages.
OTLP ingestion became normal. Langfuse, MLflow, promptfoo, TruLens and DeepEval all accept or export OpenTelemetry traces. Two attribute vocabularies compete on top of the transport.
OpenInference leads in practice. Arize's vocabulary draws 8.6 million monthly downloads.[138][138] OpenInference conventions downloads pypistats Primary It instruments the OpenAI Agents SDK, the Claude Agent SDK, LangChain and AutoGen, and ships a bridge for OpenLLMetry.[147][147] OpenInference README Primary The vocabularies therefore seem to converge.
The official GenAI conventions are still a draft. They moved out of the core OpenTelemetry repo in 2026 and cover inference, retrieval, agent spans and MCP.[141][141] Core GenAI README OpenTelemetry Primary[142][142] GenAI conventions overview OpenTelemetry Primary Their status stays "Development", and the schema URL section still reads "TODO".
Three trace vocabularies on top of OpenTelemetry
| Standard | Maintainer | Licence | Adoption signal | Status |
|---|---|---|---|---|
| OTel GenAI semantic conventions[136][136] OTel GenAI conventions GitHub API Primary | OpenTelemetry | Apache-2.0 | 523 stars; new repo since May 2026 | "Development", no release yet |
| OpenInference[137][137] OpenInference GitHub Primary | Arize (Dynatrace) | Apache-2.0 | 1,305 stars; 8.6M monthly downloads[138][138] OpenInference conventions downloads pypistats Primary | Active, widest instrumentation |
| OpenLLMetry[139][139] OpenLLMetry GitHub Primary | Traceloop (ServiceNow) | Apache-2.0 | 7,522 stars; 1.8M monthly downloads[140][140] traceloop-sdk downloads pypistats Primary | Active, release on 5 Nov 2026 |
A neutral slot for eval scores now exists. The gen_ai.evaluation.result event carries a name, a score, a label and an explanation on the evaluated span.[145][145] GenAI events OpenTelemetry Primary It is the first neutral way to put eval scores on production traces. Judge model, rubric version and confidence intervals still need custom attributes.
No result format has won. Inspect writes binary .eval logs, about one eighth the size of JSON, with access to single samples.[149][149] Inspect eval logs docs UK AISI Primary Many projects read or export this format, so it acts as the richest de facto format. The neutral alternative barely registers.
The two candidate result formats
| Feature | Inspect .eval logs (UK AISI) | Every Eval Ever (EvalEval Coalition) |
|---|---|---|
| Format | Binary .eval files, default since v0.3.46 | Shared schema, instance-level JSONL |
| Size | About 1/8 the size of JSON | Not stated |
| Single-sample access | Yes | Yes |
| Agentic samples with tool calls | Yes | Yes |
| Shared results database | No | Crowdsourced database |
| Reads other harnesses | Many projects read or export it | Converters for Inspect, HELM, lm-eval |
| Cloud storage | S3 or Azure | Not stated |
| Uptake signal | Richest de facto format | 285 PyPI downloads last month |
285
PyPI downloads last month for Every Eval Ever, the neutral eval result schema. Inspect AI drew 2.9 million.
Source: pypistats (5 Nov 2026).[151][151] every-eval-ever downloads pypistats Primary[3][3] inspect-ai downloads pypistats Primary
ClickHouse became the default trace store. Langfuse, Opik and self-managed Weave all run on it.[84][84] Self-hosting docs Langfuse Primary[87][87] Self-host architecture Opik Primary[89][89] Weave self-managed docs CoreWeave Primary ClickHouse also bought Langfuse in January 2026. Datasets mostly live on Hugging Face, and Langfuse versions its datasets on every change.[148][148] Datasets docs Langfuse Primary
MCP became the common way for eval agents to reach tools. Inspect, verifiers, OpenEnv, Harbor and promptfoo all support MCP tools. The spec has five dated versions, from November 2024 to July 2026.[152][152] Schema folder MCP Primary The project is moving from MIT to Apache-2.0 for code and spec.[153][153] LICENSE MCP Primary
-
- Agent spans. The GenAI conventions define
create_agent,invoke_agentandinvoke_workflow. The last fits apps that define their own control flow, such as LangGraph.[144][144] GenAI agent spans OpenTelemetry Primary - Core conventions. The core OpenTelemetry semantic conventions repo reached v1.45.0 on 2 November 2026.[143][143] Semantic conventions releases OpenTelemetry Primary
- OpenInference span kinds. Every span needs a kind, such as LLM, TOOL, AGENT, GUARDRAIL or EVALUATOR.[146][146] Semantic conventions OpenInference Primary
- MCP spans. OpenTelemetry adds span conventions for MCP calls.[154][154] MCP conventions OpenTelemetry Primary promptfoo ships an MCP red-team plugin.
- MCP licence. Docs move to CC-BY-4.0, code and spec to Apache-2.0.[153][153] LICENSE MCP Primary
- Datasets. lm-evaluation-harness and SWE-bench load tasks from Hugging Face Datasets.
- Agent spans. The GenAI conventions define
Docker is the sandbox contract, but judges and statistics still lack standards
Three supporting layers decide how far readers can trust a result. They cover where the agent runs, who grades it and how sure the number is.
Docker became the universal sandbox contract. Inspect ships Docker and local sandboxes, and external packages add Kubernetes, Daytona, Modal, EC2 and Proxmox.[155][155] Inspect sandboxing docs UK AISI Primary Harbor runs on nine cloud back ends, and OpenEnv runs each environment as a Docker image. Cloud vendors now compete as interchangeable back ends.
Check Daytona's licence before you build on it. Daytona has 71,377 GitHub stars, but the GitHub API reports no licence, and our research did not confirm one.[159][159] Daytona GitHub Primary
Most harnesses call models through an OpenAI-compatible API. vLLM serves open models behind that API, with over 96,000 stars under Apache-2.0.[160][160] vLLM GitHub Primary Teams can serve open judge models through vLLM to cut grading costs.
LLM judges now grade most open-ended answers. Every framework ships judge templates, and open guard models give a cheaper option.[161][161] Granite Guardian 4.1 8B model card IBM Primary[162][162] Qwen3Guard models Hugging Face API Primary[163][163] Llama Guard 4 model card Meta Primary No open judge publishes human agreement on agent transcripts in a regulated domain. Most published numbers compare judges with GPT-4-class labels, not with human experts.
Open judge and guard models
| Model | Maintainer | Licence | Signal | Note |
|---|---|---|---|---|
| Granite Guardian 4.1 8B[161][161] Granite Guardian 4.1 8B model card IBM Primary | IBM | Apache-2.0 | 10k downloads in 30 days | Custom criteria, groundedness, function-call checks |
| Qwen3Guard[162][162] Qwen3Guard models Hugging Face API Primary | Alibaba | Apache-2.0 | 223k downloads (0.6B size) | Safety in 119 languages |
| Llama Guard 4 12B[163][163] Llama Guard 4 model card Meta Primary | Meta | Llama 4 Community License | 88k downloads | MLCommons hazard taxonomy |
Averaging judges is a cheap gain. Composo found that averaging eight judge scores added 9.8 points on RewardBench 2. Three scores gave most of that gain.[164][164] Judge ensembling paper Composo Primary
Statistics remain the weakest layer. Most CI gates still compare a pass rate with a fixed threshold. Inspect offers the best single-run intervals and supports early stopping.[29][29] Inspect metrics docs UK AISI Primary[165][165] Inspect early stopping docs UK AISI Primary MLflow alone ships a paired test.[86][86] Comparing evaluation runs MLflow Primary No tool combines paired tests, non-inferiority margins and monitoring over time.
How Many Test Cases Does a Trustworthy Pass Rate Need?
Move the sliders. Most CI gates compare one pass rate with a threshold and never show this margin.
test cases needed
683
independent test cases for a 95% interval
1.96² × 0.80 × 0.20 × 1.0 ÷ 0.030² = 683
Cases needed (log scale) by margin of error, in points
n = 1.96² × p × (1 − p) × design effect ÷ margin². A pass rate near 80%, measured to ±3 points, needs about 683 independent cases.
Which tools ship which statistics
| Tool | Single-run intervals | Judge agreement | Sequential / early stopping | Paired test | Item-response model | Non-inferiority margin | Drift over time |
|---|---|---|---|---|---|---|---|
| Inspect AI | Yes: stderr, bootstrap, Wilson, clustered | Yes: Krippendorff's alpha | Yes | No | n/a | No | No |
| MLflow 3.18 | Yes: bootstrap | n/a | n/a | Yes: McNemar, Wilcoxon | n/a | No | No |
| NeMo Evaluator | Yes: via scipy | n/a | n/a | No | n/a | No | No |
| Epoch AI ECI | n/a | n/a | n/a | n/a | Yes: Bayesian IRT | No | No |
| Typical CI gate (most app eval tools) | No: pass rate vs threshold | No | No | No | No | No | No |
-
Project Maintainer Licence Stars Status Role E2B[156][156] E2B GitHub Primary E2B Apache-2.0 14,721 Very active Cloud sandboxes for agents gVisor[157][157] gVisor GitHub Primary Google Apache-2.0 19,875 Active Strong container isolation Modal client[158][158] Modal client GitHub Primary Modal Apache-2.0 (client only) 533 Active Serverless sandboxes, closed platform Daytona[159][159] Daytona GitHub Primary Daytona not reported by the API 71,377 Last push 24 Jul 2026 Cloud sandboxes for agents Table 10. GitHub API, 5 Nov 2026. Harbor's back ends: local Docker, Daytona, Modal, LangSmith, Blaxel, Novita, Tensorlake, Runta and Sail.[31][31] Harbor README Primary The lm-evaluation-harness README recommends vLLM's server for large models. OpenCompass added a LiteLLM gateway in 2026.[37][37] OpenCompass README Primary
Larger companies bought most eval platforms in 2026, and no open licence changed
2026 was the consolidation year for eval and observability tools. Data platforms, observability vendors, security vendors and model labs bought most independent players.
Seven deals touched open eval projects between January and October 2026. ClickHouse bought Langfuse on 16 January.[168][168] Langfuse acquisition ClickHouse Vendor OpenAI bought promptfoo, ServiceNow bought Traceloop, and Cisco closed Galileo in May.[73][73] Joining OpenAI promptfoo Vendor[170][170] Joining ServiceNow Traceloop Vendor[171][171] Galileo acquisition Cisco Vendor Dynatrace closed its purchase of Arize, the owner of Phoenix, on 1 October.[175][175] Dynatrace completes Arize deal engineering.com Secondary
Platforms, Security Vendors and Labs Bought the Eval Tools
Deals for eval, observability and AI-security tools, June 2025 to October 2026, by type of buyer. Bold: the four 2026 data-platform deals.
Data table
| Date | Lane | Event | Kind | Note |
|---|---|---|---|---|
| 2025-06 | Security vendors | Snyk buys Invariant Labs | acquired | |
| 2025-08 | Model labs | Humanloop team joins Anthropic | acquired | Team move, not a company purchase |
| 2025-09 | Security vendors | Check Point buys Lakera | acquired | |
| 2025-11 | Security vendors | Zscaler buys SPLX | acquired | |
| 2026-01-16 | Data and observability platforms | ClickHouse buys Langfuse | acquired | Core stays MIT |
| 2026-03 | Data and observability platforms | ServiceNow buys Traceloop | acquired | OpenLLMetry stays open |
| 2026-03-03 | Other buyers | Mintlify buys Helicone | acquired | Hosted product in maintenance |
| 2026-03-09 | Model labs | OpenAI buys promptfoo | acquired | Closed; stays MIT |
| 2026-05 | Security vendors | Check Point buys Deepchecks team and IP | acquired | Up to $20M (press estimate) |
| 2026-05-22 | Data and observability platforms | Cisco closes Galileo | acquired | Becomes Splunk Agent Observability |
| 2026-05-29 | Security vendors | Palo Alto Networks closes Portkey | acquired | AI gateway of Prisma AIRS |
| 2026-06-15 | Security vendors | A10 Networks buys TrojAI | acquired | |
| 2026-09 | Other buyers | Beacon Software buys Haize Labs | acquired | Software roll-up |
| 2026-10-01 | Data and observability platforms | Dynatrace closes Arize (Phoenix) | acquired | $915M reported |
Buyers fall into three groups. ClickHouse, Dynatrace, Cisco with Splunk, and ServiceNow wanted traces and evals for their platforms. Palo Alto Networks, Check Point, Zscaler, A10 Networks and Snyk wanted AI security tools. OpenAI bought promptfoo, and Anthropic took the Humanloop team.[179][179] Humanloop team joins Anthropic Data Phoenix Secondary
Most prices stayed private. Dynatrace paid a reported $915M for Arize, about $815M of it in cash.[173][173] Arize acquisition Dynatrace Vendor[174][174] Dynatrace and Arize ITPro Secondary Calcalist reported $60–80M for Traceloop, but nobody confirmed it.[183][183] Traceloop price Calcalist Single source Press estimates put the Deepchecks price at up to $20M.[184][184] Deepchecks price Dealroom citing Calcalist Estimate
Ownership changed, but licences did not. No eval project in scope moved to a BSL or AGPL licence in 2025 or 2026. No acquirer changed an open licence after a deal. promptfoo stays MIT under OpenAI, and Langfuse's core stays MIT under ClickHouse.[74][74] promptfoo README Primary[168][168] Langfuse acquisition ClickHouse Vendor
Most Eval Code Can Be Hosted for Others; Phoenix Cannot
What each licence lets a team do with the code, November 2026. A reading of licence files, not legal advice.
| Project (licence) | Use internally | Change the code | Embed and redistribute | Host as a service for others |
|---|---|---|---|---|
| Inspect AI, lm-eval, promptfoo, PyRIT MIT | Allowed | Allowed | Allowed | Allowed |
| Harbor, DeepEval, Opik, MLflow, garak Apache-2.0 | Allowed | Allowed | Allowed | Allowed |
| OpenEnv BSD-3-Clause | Allowed | Allowed | Allowed | Allowed |
| verifiers, tau2-bench, Giskard, Scenario MIT or Apache-2.0 | Allowed | Allowed | Allowed | Allowed |
| Langfuse, Agenta MIT core + closed ee/ | Allowed | With limits core only | With limits core only | With limits license ee/ features |
| Change the code: core onlyEmbed and redistribute: core onlyHost as a service for others: license ee/ features | ||||
| LangWatch Apache core + enterprise/ | Allowed | With limits core only | With limits core only | With limits SSO, audit logs, billing closed |
| Change the code: core onlyEmbed and redistribute: core onlyHost as a service for others: SSO, audit logs, billing closed | ||||
| Arize Phoenix server, phoenix-evals Elastic License 2.0 | Allowed | With limits within ELv2 terms | With limits client + OTel packages are Apache-2.0 | Not allowed no hosted or managed service |
| Change the code: within ELv2 termsEmbed and redistribute: client + OTel packages are Apache-2.0Host as a service for others: no hosted or managed service | ||||
| Kiln desktop app Fair-code (library MIT) | With limits read terms | With limits read terms | With limits read terms | With limits read terms before commercial use |
| Use internally: read termsChange the code: read termsEmbed and redistribute: read termsHost as a service for others: read terms before commercial use | ||||
| LangSmith, Braintrust, Weave server, Modal Open SDK, closed platform | With limits SDK; back end is paid | With limits SDK only | With limits SDK only | Not allowed |
| Use internally: SDK; back end is paidChange the code: SDK onlyEmbed and redistribute: SDK only | ||||
| MCP MIT → Apache-2.0 | Allowed | Allowed | Allowed | Allowed |
| Daytona No licence reported | Unknown or not applicable | Unknown or not applicable | Unknown or not applicable | Unknown or not applicable check before building |
| Host as a service for others: check before building | ||||
What to notice
- Read the shaded column: Phoenix's Elastic License is the only open licence here that forbids hosting.
Evals now sit inside bigger suites. Buyers should expect roadmaps to bend toward the parent platform. Several projects also moved home without a sale: Harbor, OpenEnv, Petri and Ragas changed GitHub organisations.
Venture Money Backs Most of the Remaining Independents
Thirteen open eval projects and companies that no acquirer owns, by type of backer, November 2026. One square is one project.
- 7 projects Venture capital
- 3 projects Governments and nonprofits
- 3 projects Large labs and tech firms
Each square is 1 of 13 projects.
Data table
| Group | Value |
|---|---|
| Venture capital | 7 projects |
| Governments and nonprofits | 3 projects |
| Large labs and tech firms | 3 projects |
-
Date Target Buyer Effect on the open project 16 Jan 2026 Langfuse[168][168] Langfuse acquisition ClickHouse Vendor ClickHouse Core stays MIT, cloud continues 3 Mar 2026 Helicone[169][169] Helicone acquisition Mintlify Vendor Mintlify Hosted product in maintenance mode 9 Mar 2026 (now closed) promptfoo[73][73] Joining OpenAI promptfoo Vendor OpenAI Stays open source under MIT[74][74] promptfoo README Primary Mar 2026 Traceloop (OpenLLMetry)[170][170] Joining ServiceNow Traceloop Vendor ServiceNow OpenLLMetry stays open, joins AI Control Tower 22 May 2026 (close) Galileo[171][171] Galileo acquisition Cisco Vendor Cisco Becomes Splunk Agent Observability 29 May 2026 (close) Portkey[172][172] Portkey acquisition Palo Alto Networks Vendor Palo Alto Networks Becomes the AI gateway of Prisma AIRS 1 Oct 2026 (close) Arize (Phoenix)[173][173] Arize acquisition Dynatrace Vendor Dynatrace Phoenix and AX continue, reported $915M[174][174] Dynatrace and Arize ITPro Secondary[175][175] Dynatrace completes Arize deal engineering.com Secondary Table 11. 2026 deals that touched open eval projects. Licence model Projects What you can do Permissive (MIT, Apache-2.0, BSD) Inspect, lm-evaluation-harness, Harbor, promptfoo, DeepEval, DeepTeam, Opik, MLflow, garak, PyRIT, verifiers, OpenEnv, tau2-bench, Giskard, Scenario Use, change, embed and host as a service Open core with closed ee/folderLangfuse, Agenta, LangWatch Use the MIT or Apache core freely, but license the enterprise parts Source-available (Elastic License 2.0) Phoenix server and phoenix-evalsUse internally, but do not offer it as a hosted service Fair-code Kiln desktop app Read the terms before commercial use Open SDK, closed platform LangSmith, Braintrust, Weave server, Modal Use the SDK, but the back end stays a paid product Licence in transition MCP, from MIT to Apache-2.0 Expect more permissive terms Table 12. Licence models across the eval stack. Guidance for hosted offers. A team that wants to host evals for others should prefer the permissive projects. It should avoid hosting Phoenix as a service.[88][88] LICENSE Arize Phoenix Primary It should keep Langfuse and LangWatch enterprise features out of any hosted offer without a licence.[166][166] LICENSE Langfuse Primary[167][167] Enterprise LICENSE LangWatch Primary
Earlier and smaller deals. CoreWeave now owns W&B and hosts the Weave docs.[89][89] Weave self-managed docs CoreWeave Primary Check Point bought the Deepchecks team and IP in 2026.[180][180] Check Point and Deepchecks Security Boulevard Secondary Dynatrace paid about $815M of the $915M in cash and the rest in replacement equity.[173][173] Arize acquisition Dynatrace Vendor
Standardise on the plumbing; results, judges and statistics are still open ground
The table sums up what a team can treat as settled today and what still moves.
The lower layers are safe to standardise on. Docker, OpenAI-compatible APIs, OpenTelemetry and MCP will likely stay.
The harness choice depends on the job. Inspect suits agentic and safety work, lm-evaluation-harness suits open weights, and Harbor suits container tasks.
The upper layers still lack standards. Result formats, judge validation and contract-grade statistics remain open. Lab-owned red-team tools also raise a neutrality question.
Standard today, still open
| Area | Standard today | Still open |
|---|---|---|
| Model benchmarks | Inspect and lm-evaluation-harness | Funding for leaderboards and static benchmarks |
| Agent tasks | Harbor folder with Dockerfile and test script | Cost and speed of large container runs |
| Environment API | OpenEnv reset, step, state | Size and quality of shared hubs |
| Sandboxes | Docker images | Isolation standards and vendor choice |
| Tool access | MCP | Final licence and versioning |
| Trace transport | OpenTelemetry OTLP | None |
| Trace vocabulary | OpenInference in practice | OTel GenAI conventions still "Development" |
| Eval results on traces | gen_ai.evaluation.result event | Judge, rubric and interval metadata |
| Result exchange | Inspect .eval logs in practice | Every Eval Ever uptake |
| Judges | LLM judges in every framework | Human agreement data for agent transcripts |
| Statistics | Threshold gates and single-run intervals | Paired tests, non-inferiority and drift over time |
| Red team | promptfoo, garak, PyRIT | Neutrality of lab-owned tools |
Sources
Every number keeps its date and source. Badges mark source quality: primary, secondary, vendor (a claim about the publisher's own product), single source, or estimate.
- [1] swebench downloads, pypistats. It gives the monthly PyPI download count for SWE-bench. Primary pypistats.org
- [2]
- [3]
- [4]
- [5]
- [6]
- [7]
- [8] Harbor, GitHub API. It gives stars, licence and the move from laude-institute. Primary api.github.com
- [9]
- [10]
- [11]
- [12]
- [13]
- [14]
- [15]
- [16]
- [17]
- [18]
- [19]
- [20]
- [21]
- [22] Inspect docs folder, UK AISI. It covers tasks, scorers, agents, the agent bridge and MCP tools. Primary github.com
- [23] Meridian Labs repos, GitHub search. It lists the Inspect add-ons and Petri projects. Primary github.com
- [24] inspect_evals README. It names Generality Labs as maintainer and sets contributor rules. Primary github.com
- [25]
- [26] NeMo Evaluator README, NVIDIA. It lists interceptors, confidence intervals and Inspect export. Primary github.com
- [27]
- [28] Eval Results, Hugging Face Hub docs. It defines a verified result as an Inspect run in HF Jobs. Primary huggingface.co
- [29] Inspect metrics docs, UK AISI. It lists the error, interval and agreement metrics. Primary github.com
- [30] lm-evaluation-harness README, EleutherAI. It covers YAML tasks, plugins, backends and named users. Primary github.com
- [31] Harbor README. It describes agents, cloud providers and the Terminal-Bench 2.0 role. Primary github.com
- [32]
- [33]
- [34]
- [35]
- [36]
- [37]
- [38] Capabilities Index package, Epoch AI. It describes the Bayesian item-response fit. Primary github.com
- [39]
- [40] Maintenance mode policy, HELM. It explains what the team still maintains. Primary crfm-helm.readthedocs.io
- [41]
- [42]
- [43] HAL harness README, Princeton PLI. It states that the repo stays archived for reference. Primary github.com
- [44] End of the Open LLM Leaderboard, Hugging Face. It announces the retirement on 13 March 2025. Primary huggingface.co
- [45] Leaderboards docs, Hugging Face. It describes the Open LLM Leaderboard in the past tense. Primary huggingface.co
- [46]
- [47]
- [48]
- [49]
- [50]
- [51]
- [52]
- [53]
- [54]
- [55]
- [56]
- [57]
- [58]
- [59]
- [60]
- [61]
- [62]
- [63]
- [64]
- [65]
- [66]
- [67]
- [68]
- [69]
- [70]
- [71]
- [72]
- [73]
- [74] promptfoo README. It states that Promptfoo now belongs to OpenAI and stays MIT-licensed. Primary github.com
- [75]
- [76]
- [77]
- [78]
- [79]
- [80]
- [81] Braintrust Series B, SiliconANGLE. It reports the $80M round, as a secondary source. Secondary siliconangle.com
- [82]
- [83]
- [84]
- [85]
- [86] Comparing evaluation runs, MLflow. It describes the paired tests between two runs. Primary github.com
- [87]
- [88]
- [89] Weave self-managed docs, CoreWeave. It describes Weave on ClickHouse under CoreWeave. Primary docs.coreweave.com
- [90]
- [91]
- [92]
- [93]
- [94]
- [95]
- [96]
- [97]
- [98]
- [99]
- [100]
- [101] appworld downloads, pypistats. It gives a monthly count that likely includes CI pulls. Primary pypistats.org
- [102]
- [103]
- [104]
- [105] inspect_petri, GitHub API. It gives stars, licence and the move from safety-research. Primary api.github.com
- [106]
- [107] verifiers README, Prime Intellect. It describes the library and its links to the Hub. Primary github.com
- [108] verifiers overview, Prime Intellect. It defines tasksets, harnesses, agents and toolsets. Primary github.com
- [109]
- [110] Post on X, Prime Intellect. It claims over 400 crowdsourced environments in October 2025. Single source threadreaderapp.com
- [111] tau2-bench README, Sierra. It describes version 2.0, languages, voice and task counts. Primary github.com
- [112]
- [113]
- [114]
- [115]
- [116] ControlArena repository. It describes the AI control library from UK AISI and Redwood. Primary github.com
- [117]
- [118]
- [119]
- [120]
- [121]
- [122]
- [123]
- [124]
- [125] Red-team configuration, promptfoo. It describes remote and local attack generation. Primary github.com
- [126] garak README, NVIDIA. It describes probes, detectors, harnesses and the REST generator. Primary github.com
- [127]
- [128]
- [129]
- [130]
- [131]
- [132]
- [133]
- [134] OWASP AI Testing Guide. It gives a method for testing the trustworthiness of AI systems. Primary owasp.org
- [135] Top 10 for Agentic Applications for 2026, OWASP. It lists the main security risks of agentic applications. Primary genai.owasp.org
- [136] OTel GenAI conventions, GitHub API. It gives the creation date, stars and licence. Primary api.github.com
- [137]
- [138] OpenInference conventions downloads, pypistats. It gives the monthly PyPI download count. Primary pypistats.org
- [139]
- [140]
- [141] Core GenAI README, OpenTelemetry. It states that the GenAI conventions moved to a new repo. Primary github.com
- [142]
- [143]
- [144]
- [145]
- [146]
- [147]
- [148]
- [149] Inspect eval logs docs, UK AISI. It describes the .eval format and storage options. Primary github.com
- [150] Every Eval Ever README, EvalEval. It describes the schema, the database and the converters. Primary github.com
- [151] every-eval-ever downloads, pypistats. It gives the monthly PyPI download count. Primary pypistats.org
- [152]
- [153]
- [154]
- [155]
- [156]
- [157]
- [158]
- [159]
- [160]
- [161] Granite Guardian 4.1 8B model card, IBM. It gives criteria, scores and the licence. Primary huggingface.co
- [162]
- [163]
- [164] Judge ensembling paper, Composo. It measures the gain from criteria and ensembles. Primary arxiv.org
- [165] Inspect early stopping docs, UK AISI. It describes early stopping and optional stopping. Primary github.com
- [166]
- [167]
- [168] Langfuse acquisition, ClickHouse. It announces the deal and the licence pledge. Vendor clickhouse.com
- [169]
- [170] Joining ServiceNow, Traceloop. It announces the deal and the open-source pledge. Vendor traceloop.com
- [171]
- [172]
- [173]
- [174]
- [175] Dynatrace completes Arize deal, engineering.com. It reports the close on 1 October 2026. Secondary engineering.com
- [176]
- [177]
- [178]
- [179]
- [180] Check Point and Deepchecks, Security Boulevard. It reports the purchase of the Deepchecks team and IP. Secondary securityboulevard.com
- [181]
- [182] Beacon Software and Haize Labs, Osler. It describes the deal and the new research group. Secondary osler.com
- [183]
- [184] Deepchecks price, Dealroom citing Calcalist. It estimates the price at up to $20M. Estimate dealroom.co
All figure and table data in this chapter. Each item links to its place in the report.
Figure 1. The Sandbox and the Harness Have Settled. Grading and Reporting Have Not.
| Layer | State | Tool or leader | Adoption | Date | Licence | Source |
|---|---|---|---|---|---|---|
| 7 · Reporting | Fragmented | Leaderboards (Epoch AI hub, Artificial Analysis, LMArena) | ||||
| 7 · Reporting | Fragmented | Dashboards | Langfuse 23.6M and MLflow 19.9M PyPI downloads a month, incl. SDK installs | 5 Nov 2026 | pypistats | |
| 7 · Reporting | Fragmented | Lab system cards (Each lab picks its own benchmarks) | ||||
| 6 · Traces and storage | Draft | OTel GenAI conventions (Status "Development") | OpenTelemetry docs | |||
| 6 · Traces and storage | Draft | OpenInference (Leads in practice) | 8.6M downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 5 · Statistics | Fragmented | Confidence intervals (Inspect) | ||||
| 5 · Statistics | Fragmented | Item-response models (Epoch AI) | ||||
| 5 · Statistics | Fragmented | pass^k (Success on all k tries) | ||||
| 5 · Statistics | Fragmented | Sequential tests (Stop early when the answer is clear) | ||||
| 4 · Graders | Fragmented | autoevals (Braintrust) | 4.1M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | DeepEval (Confident AI) | 2.6M PyPI downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 4 · Graders | Fragmented | Ragas (No commits since 24 Feb 2026) | 1.1M PyPI downloads a month | 5 Nov 2026 | Apache-2.0 | pypistats |
| 4 · Graders | Fragmented | openevals (LangChain) | 1.0M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | agentevals (LangChain) | 428k PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 4 · Graders | Fragmented | TruLens | 20k PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 3 · Harness or runner | Standard | Inspect AI (UK AISI) | 2.9M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 3 · Harness or runner | Standard | lm-evaluation-harness (EleutherAI) | 1.0M PyPI downloads a month | 5 Nov 2026 | MIT | pypistats |
| 2 · Environments and sandboxes | Standard | Docker (Every major harness runs tasks in Docker containers) | ||||
| 2 · Environments and sandboxes | Standard | E2B · Modal · Daytona (Interchangeable cloud back ends) | ||||
| 1 · Tasks and datasets | Fragmented | Harbor task folders | 4.8M PyPI downloads a month (Harbor) | 5 Nov 2026 | Apache-2.0 | pypistats |
| 1 · Tasks and datasets | Fragmented | lm-eval YAML | 1.0M PyPI downloads a month (lm-evaluation-harness) | 5 Nov 2026 | MIT | pypistats |
| 1 · Tasks and datasets | Fragmented | Inspect tasks | 867k PyPI downloads a month (inspect_evals) | 5 Nov 2026 | MIT | pypistats |
| 1 · Tasks and datasets | Fragmented | Hugging Face Datasets (Shared dataset hub; no comparable count, so tiles in this layer are equal) |
Figure 2. The Most-Starred Harnesses Are Not the Most Used
| Point | GitHub stars | Monthly PyPI downloads (thousands) | Category | Note |
|---|---|---|---|---|
| Harbor | 6821 | 4,800k | Very active or active | 4.8M a month |
| Inspect AI | 3185 | 2,900k | Very active or active | 2.9M a month with 3,185 stars |
| lm-evaluation-harness | 14408 | 1,000k | Very active or active | Most stars, 1.0M a month |
| inspect_evals | 733 | 867k | Very active or active | |
| SWE-bench | 6149 | 22,100k | Very active or active | Mostly CI traffic |
| lighteval | 2579 | 6k | Very active or active | Likely a data gap |
| OpenCompass | 7563 | 3k | Very active or active | |
| openbench | 831 | 2k | Very active or active | |
| HELM | 2964 | 1k | Maintenance mode | Maintenance since 1 Jun 2026 |
Figure 3. Well-Known Eval Projects Freeze Every Few Months
| Date | Lane | Event | Kind | Note |
|---|---|---|---|---|
| 2024-07 | Harnesses and leaderboards | BIG-bench last push; repo archived | shutdown | |
| 2025-03-13 | Harnesses and leaderboards | Open LLM Leaderboard retired | shutdown | Results stay as datasets; Eval Results replaces it |
| 2025-07 | Harnesses and leaderboards | simple-evals frozen | shutdown | Still hosts HealthBench, BrowseComp, SimpleQA code |
| 2026-02-24 | App and platform tools | Ragas last commit | other | Treat as unmaintained |
| 2026-03-03 | App and platform tools | Helicone hosted product in maintenance | shutdown | After Mintlify deal |
| 2026-04 | Harnesses and leaderboards | Lakera PINT benchmark archived | shutdown | |
| 2026-06-01 | Harnesses and leaderboards | HELM enters maintenance mode | shutdown | |
| 2026-10-16 | App and platform tools | langsmith-sdk monorepo archived | other | SDKs moved to two new repos |
Figure 4. Two Platforms With Production SDKs Dwarf the Eval Libraries
| Item | Value | Category |
|---|---|---|
| Langfuse (ClickHouse · MIT + closed ee/) | 23.6M | Trace-and-eval platform |
| MLflow (Databricks-led · Apache-2.0) | 19.9M | Trace-and-eval platform |
| autoevals (Braintrust · MIT) | 4.1M | Code-first library |
| promptfoo (npm) (OpenAI · MIT) | 3.6M | npm package |
| DeepEval (Confident AI · Apache-2.0) | 2.6M | Code-first library |
| Opik (Comet · Apache-2.0) | 1.7M | Trace-and-eval platform |
| Ragas (VibrantLabs · Apache-2.0) | 1.1M | Code-first library |
| openevals (LangChain · MIT) | 1.0M | Code-first library |
| Evidently (Evidently AI · Apache-2.0) | 823k | Trace-and-eval platform |
| W&B Weave (CoreWeave · Apache-2.0 SDK) | 817k | Trace-and-eval platform |
| Arize Phoenix (Dynatrace · Elastic-2.0) | 626k | Trace-and-eval platform |
| agentevals (LangChain · MIT) | 428k | Code-first library |
| LangWatch Scenario (LangWatch · Apache-2.0) | 128k | Code-first library |
| TruLens (TruEra · MIT) | 20k | Code-first library |
| Giskard v3 (Giskard · Apache-2.0) | 13k | Code-first library |
| Agenta (Agenta · MIT + closed ee/) | 13k | Trace-and-eval platform |
Figure 5. Every Tool Gates CI, but Only MLflow Runs a Paired Test
| Tool | CI pass/fail gate | OpenTelemetry traces | Simulated users | Trajectory checks | Paired test vs baseline |
|---|---|---|---|---|---|
| promptfoo | Documented (GitHub Action before/after) | Documented (OTLP receiver) | Not stated in our sources | Documented (checks against traces) | Not offered |
| DeepEval | Documented (deepeval test run) | Documented (exporter) | Documented (conversation simulator) | Limited (tool correctness, plan adherence) | Not offered |
| Langfuse | Documented | Documented (OTel endpoint) | Not stated in our sources | Not stated in our sources | Not offered |
| MLflow | Documented | Documented | Not stated in our sources | Not stated in our sources | Documented (McNemar / Wilcoxon + bootstrap) |
| Arize Phoenix | Documented | Documented (OpenInference) | Not stated in our sources | Not stated in our sources | Not offered |
| TruLens | Documented | Documented | Not stated in our sources | Not stated in our sources | Not offered |
| LangWatch Scenario | Documented | Not stated in our sources | Documented (simulated user + judge) | Not stated in our sources | Not offered |
| agentevals | Documented | Not stated in our sources | Not stated in our sources | Documented (4 match modes) | Not offered |
Figure 6. One Agent Task Now Serves as a Test and as Training Data
| Step | Stage | What happens | Example |
|---|---|---|---|
| 1 | Write the task | A Harbor folder: instruction.md, task.toml, environment/Dockerfile, optional solution, tests/test.sh. | A Terminal-Bench 2 task |
| 2 | Start the world | The Dockerfile builds a sandbox; OpenEnv calls reset() over a WebSocket. | Local Docker, Daytona, Modal or a Hugging Face Space |
| 3 | The agent acts | A harness drives the model through step() calls; tools arrive over MCP. | Claude Code, Codex or OpenHands |
| 4 | Score the outcome | The task's test script or a verifiers rubric grades the final state. | tests/test.sh returns pass or fail |
| 5 | Keep the trace | Inspect writes an .eval log; the OpenEnv–Harbor integration keeps the exact tokens. | Binary log about 1/8 the size of JSON |
| 6 | Use it as an eval score | The pass rate goes to a leaderboard, a system card or a CI gate. | Terminal-Bench 2.0 leaderboard |
| 7 | Use it as an RL reward | The same rollout and score feed an RL trainer. | TRL, Unsloth, SkyRL, ART or prime-rl |
Figure 7. Four Open Projects Join Evaluation and Training
| title | tag | keyNumber | keyLabel | color |
|---|---|---|---|---|
| Harbor | Tasks and sandboxes | 86 | benchmark adapters | indigo |
| OpenEnv | Step API and hosting | 40+ | ready-made environments | teal |
| verifiers | Rubrics and training | 762k | monthly PyPI downloads | sage |
| Inspect AI | Logging and scoring | 200+ | ready-made evaluations | purple |
Figure 8. promptfoo Dwarfs the Other Open Red-Team Tools in Downloads
| Item | Value | Note |
|---|---|---|
| promptfoo | 3.6M | OpenAI · MIT · npm, whole package |
| PyRIT | 72k | Microsoft · MIT |
| DeepTeam | 71k | Confident AI · Apache-2.0 |
| garak | 39k | NVIDIA · Apache-2.0 |
Figure 9. How Many Test Cases Does a Trustworthy Pass Rate Need?
| id | label | min | max | step | value | unit |
|---|---|---|---|---|---|---|
| margin | Margin of error (± points) | 1 | 10 | 0.5 | 3 | pts |
| accuracy | Expected pass rate | 50 | 99 | 1 | 80 | % |
| designEffect | Design effect (clustered cases) | 1 | 3 | 0.1 | 1 |
Figure 10. Platforms, Security Vendors and Labs Bought the Eval Tools
| Date | Lane | Event | Kind | Note |
|---|---|---|---|---|
| 2025-06 | Security vendors | Snyk buys Invariant Labs | acquired | |
| 2025-08 | Model labs | Humanloop team joins Anthropic | acquired | Team move, not a company purchase |
| 2025-09 | Security vendors | Check Point buys Lakera | acquired | |
| 2025-11 | Security vendors | Zscaler buys SPLX | acquired | |
| 2026-01-16 | Data and observability platforms | ClickHouse buys Langfuse | acquired | Core stays MIT |
| 2026-03 | Data and observability platforms | ServiceNow buys Traceloop | acquired | OpenLLMetry stays open |
| 2026-03-03 | Other buyers | Mintlify buys Helicone | acquired | Hosted product in maintenance |
| 2026-03-09 | Model labs | OpenAI buys promptfoo | acquired | Closed; stays MIT |
| 2026-05 | Security vendors | Check Point buys Deepchecks team and IP | acquired | Up to $20M (press estimate) |
| 2026-05-22 | Data and observability platforms | Cisco closes Galileo | acquired | Becomes Splunk Agent Observability |
| 2026-05-29 | Security vendors | Palo Alto Networks closes Portkey | acquired | AI gateway of Prisma AIRS |
| 2026-06-15 | Security vendors | A10 Networks buys TrojAI | acquired | |
| 2026-09 | Other buyers | Beacon Software buys Haize Labs | acquired | Software roll-up |
| 2026-10-01 | Data and observability platforms | Dynatrace closes Arize (Phoenix) | acquired | $915M reported |
Figure 11. Most Eval Code Can Be Hosted for Others; Phoenix Cannot
| Project (licence) | Use internally | Change the code | Embed and redistribute | Host as a service for others |
|---|---|---|---|---|
| Inspect AI, lm-eval, promptfoo, PyRIT | Allowed | Allowed | Allowed | Allowed |
| Harbor, DeepEval, Opik, MLflow, garak | Allowed | Allowed | Allowed | Allowed |
| OpenEnv | Allowed | Allowed | Allowed | Allowed |
| verifiers, tau2-bench, Giskard, Scenario | Allowed | Allowed | Allowed | Allowed |
| Langfuse, Agenta | Allowed | With limits (core only) | With limits (core only) | With limits (license ee/ features) |
| LangWatch | Allowed | With limits (core only) | With limits (core only) | With limits (SSO, audit logs, billing closed) |
| Arize Phoenix server, phoenix-evals | Allowed | With limits (within ELv2 terms) | With limits (client + OTel packages are Apache-2.0) | Not allowed (no hosted or managed service) |
| Kiln desktop app | With limits (read terms) | With limits (read terms) | With limits (read terms) | With limits (read terms before commercial use) |
| LangSmith, Braintrust, Weave server, Modal | With limits (SDK; back end is paid) | With limits (SDK only) | With limits (SDK only) | Not allowed |
| MCP | Allowed | Allowed | Allowed | Allowed |
| Daytona | Unknown or not applicable | Unknown or not applicable | Unknown or not applicable | Unknown or not applicable (check before building) |
Figure 12. Venture Money Backs Most of the Remaining Independents
| Group | Value |
|---|---|
| Venture capital | 7 projects |
| Governments and nonprofits | 3 projects |
| Large labs and tech firms | 3 projects |
Table 1. Layer-by-layer summary on 5 Nov 2026.
| Layer | De facto standard | Open alternative | Watch point |
|---|---|---|---|
| Model benchmarks | Inspect AI, lm-evaluation-harness | lighteval, OpenCompass, NeMo Evaluator | HELM in maintenance mode |
| Agent benchmark tasks | Harbor task format | SWE-bench harness, OSWorld | Docker cost at scale |
| Environments for eval and RL | OpenEnv step API, verifiers | tau2-bench, AppWorld, BrowserGym | Hub sizes unverified |
| App and agent evals | DeepEval (library), promptfoo (CLI) | Giskard, openevals, LangWatch Scenario | Ragas idle since February 2026 |
| Self-hosted platform | Langfuse, MLflow | Opik, Agenta | Phoenix under ELv2 |
| Red team | promptfoo | garak, PyRIT, DeepTeam | OpenAI owns promptfoo |
| Tracing | OpenTelemetry with OpenInference attributes | OTel GenAI conventions | GenAI conventions still "Development" |
| Tool access | MCP | none | Licence move to Apache-2.0 |
| Sandboxes | Docker images | Kubernetes, Modal, Daytona, E2B | Vendor lock-in at scale |
| Result format | Inspect .eval logs | Every Eval Ever | Very low uptake |
Table 2. GitHub API and pypistats, 5 Nov 2026.
| Project | Maintainer | Licence | Stars | Monthly downloads | Status | Best for |
|---|---|---|---|---|---|---|
| Inspect AI[2][2] Inspect AI GitHub Primary | UK AISI, with Meridian Labs | MIT | 3,185 | 2.9M[3][3] inspect-ai downloads pypistats Primary | Very active | Agentic, sandboxed and safety evals |
| inspect_evals[4][4] inspect_evals GitHub Primary | Generality Labs, with UK AISI | MIT | 733 | 867k[5][5] inspect-evals downloads pypistats Primary | Very active | Ready-made evals for Inspect |
| lm-evaluation-harness[6][6] lm-evaluation-harness GitHub Primary | EleutherAI | MIT | 14,408 | 1.0M[7][7] lm-eval downloads pypistats Primary | Very active | Open-weights and log-likelihood benchmarks |
| Harbor[8][8] Harbor GitHub API Primary | Harbor Framework team (Terminal-Bench) | Apache-2.0 | 6,821 | 4.8M[9][9] harbor downloads pypistats Primary | Very active | Containerised agent benchmarks |
| SWE-bench[10][10] SWE-bench GitHub Primary | SWE-bench team (Princeton, Stanford) | MIT | 6,149 | 22.1M (CI-heavy)[1][1] swebench downloads pypistats Primary | Active | Coding-agent benchmark |
| OpenCompass[11][11] OpenCompass GitHub Primary | Shanghai AI Lab | Apache-2.0 | 7,563 | 3k | Active | Chinese and multimodal benchmarks |
| lighteval[12][12] lighteval GitHub Primary | Hugging Face | MIT | 2,579 | 6k (likely a data gap)[13][13] lighteval downloads pypistats Primary | Active, no release in 2026 | Hugging Face models and tasks |
| NeMo Evaluator[14][14] NeMo Evaluator GitHub Primary | NVIDIA | Apache-2.0 | 359 | n/a | Active | Benchmarks with interceptors |
| openbench[15][15] openbench GitHub Primary | Groq | MIT | 831 | 2k | Active | Provider benchmarks on Inspect |
| HELM[16][16] HELM GitHub Primary | Stanford CRFM | Apache-2.0 | 2,964 | 1k | Maintenance since 1 Jun 2026 | Historical comparisons |
| OpenAI Evals[17][17] OpenAI Evals GitHub Primary | OpenAI | MIT | 19,709 | n/a | Dormant | Old eval registry |
| simple-evals[18][18] simple-evals GitHub Primary | OpenAI | MIT | 4,695 | n/a | Frozen since Jul 2025 | Reference code for HealthBench, BrowseComp, SimpleQA |
| BIG-bench[19][19] BIG-bench GitHub Primary | Apache-2.0 | 3,245 | n/a | Archived | Historical tasks | |
| HAL harness[20][20] HAL harness GitHub Primary | Princeton PLI | none stated | 308 | n/a | Archived | Historical agent leaderboard |
Table 3. GitHub API, pypistats and npm, 5 Nov 2026.
| Project | Maintainer | Licence | Stars | Monthly downloads | Status | Best for |
|---|---|---|---|---|---|---|
| promptfoo[46][46] promptfoo GitHub Primary | OpenAI (acquired 2026, deal closed) | MIT | 26,875 | npm 3.6M[47][47] promptfoo downloads npm Primary | Very active | YAML evals, CI gates, red team |
| DeepEval[48][48] DeepEval GitHub Primary | Confident AI | Apache-2.0 | 19,318 | 2.6M[49][49] deepeval downloads pypistats Primary | Very active | Pytest-style tests in Python |
| Ragas[50][50] Ragas GitHub Primary | VibrantLabs | Apache-2.0 | 16,247 | 1.1M | Idle since 24 Feb 2026 | RAG metrics |
| Giskard v3[51][51] Giskard GitHub Primary | Giskard (Paris) | Apache-2.0 | 5,945 | 13k | Active, new rewrite | Multi-turn agent checks and scans |
| openevals[52][52] openevals GitHub Primary | LangChain | MIT | 1,244 | 1.0M | Active | Ready-made LLM judges |
| agentevals[53][53] agentevals GitHub Primary | LangChain | MIT | 757 | 428k | Slowing | Trajectory scoring |
| autoevals[54][54] autoevals GitHub Primary | Braintrust | MIT | 1,072 | 4.1M, npm 2.3M[55][55] autoevals downloads pypistats Primary | Active | Scorer library in Python and TS |
| TruLens[56][56] TruLens GitHub Primary | TruEra, with Snowflake ties | MIT | 3,628 | 20k | Active | Feedback functions, RAG triad |
| LangWatch Scenario[57][57] LangWatch Scenario GitHub Primary | LangWatch (Amsterdam) | Apache-2.0 | 1,015 | 128k | Active | Simulated users against agents |
| Langfuse[58][58] Langfuse GitHub Primary | ClickHouse (acquired Jan 2026) | MIT, plus closed ee/ | 37,058 | 23.6M, npm 7.7M[59][59] langfuse downloads pypistats Primary | Very active | Self-hosted traces and evals |
| MLflow[60][60] MLflow GitHub Primary | Databricks-led open project | Apache-2.0 | 28,693 | 19.9M[61][61] mlflow downloads pypistats Primary | Very active | Evals inside an ML platform |
| Opik[62][62] Opik GitHub Primary | Comet | Apache-2.0 | 23,200 | 1.7M[63][63] opik downloads pypistats Primary | Very active | Self-hosted platform, fully open |
| Arize Phoenix[64][64] Arize Phoenix GitHub Primary | Dynatrace (acquired Oct 2026) | Elastic-2.0 | 12,161 | 626k | Very active | Tracing and evals, not for resale as a service |
| W&B Weave[65][65] W&B Weave GitHub Primary | CoreWeave | Apache-2.0 (SDK only) | 1,145 | 817k | Active | Teams already on W&B |
| Evidently[66][66] Evidently GitHub Primary | Evidently AI | Apache-2.0 | 8,042 | 823k | Slowing | ML and LLM monitoring reports |
| Agenta[67][67] Agenta GitHub Primary | Agenta (Berlin) | MIT, plus closed ee/ | 4,887 | 13k | Very active | Prompt playground and evals |
| Kiln[68][68] Kiln GitHub Primary | Kiln | MIT library, source-available app | 5,255 | n/a | Active | Desktop eval and fine-tune app |
| LangSmith SDK[69][69] langsmith-sdk GitHub Primary | LangChain | MIT (platform closed) | 1,083 (old repo) | n/a | Old repo archived 16 Oct 2026 | Teams on LangSmith |
Table 4. GitHub API and pypistats, 5 Nov 2026.
| Project | Maintainer | Licence | Stars | Monthly downloads | Status | Best for |
|---|---|---|---|---|---|---|
| OpenEnv[94][94] OpenEnv GitHub API Primary | OpenEnv technical committee (Meta-PyTorch, Hugging Face and others) | BSD-3-Clause | 2,833 | 49k[95][95] openenv downloads pypistats Primary | Very active, v0.12.0 on 5 Nov 2026 | One step API for any environment |
| verifiers[96][96] verifiers GitHub Primary | Prime Intellect | MIT | 4,768 | 762k[97][97] verifiers downloads pypistats Primary | Very active | RL and eval environments, Environments Hub |
| community-environments[98][98] community-environments GitHub Primary | Prime Intellect | Apache-2.0 | 264 | n/a | Active | Shared environment library |
| tau2-bench[99][99] tau2-bench GitHub Primary | Sierra | MIT | 2,403 | n/a | Very active, v2.0.0 in Oct 2026 | Customer-service agents, text and voice |
| AppWorld[100][100] AppWorld GitHub Primary | Stony Brook NLP | Apache-2.0 | 548 | 662k (CI-heavy)[101][101] appworld downloads pypistats Primary | Active | Apps, APIs and coding agents |
| BrowserGym[102][102] BrowserGym GitHub Primary | ServiceNow Research | Apache-2.0 | 1,427 | 14k | Active | Web agents |
| AgentLab[103][103] AgentLab GitHub Primary | ServiceNow Research | Apache-2.0 | 661 | n/a | Active | Large parallel web-agent runs |
| OSWorld[104][104] OSWorld GitHub Primary | XLANG Lab (HKU) | Apache-2.0 | 3,251 | n/a | Active, no release since 2024 | Desktop computer-use agents |
| Petri[105][105] inspect_petri GitHub API Primary | Meridian Labs | MIT | 1,402 | 48k | Very active | Alignment audits with an auditor agent |
Table 5. GitHub API, pypistats and npm, 5 Nov 2026.
| Project | Maintainer | Licence | Stars | Monthly downloads | Status | Best for |
|---|---|---|---|---|---|---|
| promptfoo redteam[46][46] promptfoo GitHub Primary | OpenAI | MIT | 26,875 | npm 3.6M (whole package) | Very active | Widest plugin set, CI use |
| garak[118][118] garak GitHub Primary | NVIDIA | Apache-2.0 | 9,872 | 39k[119][119] garak downloads pypistats Primary | Very active | Scanner for any REST endpoint |
| PyRIT[120][120] PyRIT GitHub Primary | Microsoft | MIT | 4,755 | 72k[121][121] pyrit downloads pypistats Primary | Very active | Multi-turn attacks composed in code |
| DeepTeam[122][122] DeepTeam GitHub Primary | Confident AI | Apache-2.0 | 3,085 | 71k[123][123] deepteam downloads pypistats Primary | Active, last release Nov 2025 | Red team on top of DeepEval |
Table 6. Three trace vocabularies on top of OpenTelemetry
| Standard | Maintainer | Licence | Adoption signal | Status |
|---|---|---|---|---|
| OTel GenAI semantic conventions[136][136] OTel GenAI conventions GitHub API Primary | OpenTelemetry | Apache-2.0 | 523 stars; new repo since May 2026 | "Development", no release yet |
| OpenInference[137][137] OpenInference GitHub Primary | Arize (Dynatrace) | Apache-2.0 | 1,305 stars; 8.6M monthly downloads[138][138] OpenInference conventions downloads pypistats Primary | Active, widest instrumentation |
| OpenLLMetry[139][139] OpenLLMetry GitHub Primary | Traceloop (ServiceNow) | Apache-2.0 | 7,522 stars; 1.8M monthly downloads[140][140] traceloop-sdk downloads pypistats Primary | Active, release on 5 Nov 2026 |
Table 7. The two candidate result formats
| Feature | Inspect .eval logs (UK AISI) | Every Eval Ever (EvalEval Coalition) |
|---|---|---|
| Format | Binary .eval files, default since v0.3.46 | Shared schema, instance-level JSONL |
| Size | About 1/8 the size of JSON | Not stated |
| Single-sample access | Yes | Yes |
| Agentic samples with tool calls | Yes | Yes |
| Shared results database | No | Crowdsourced database |
| Reads other harnesses | Many projects read or export it | Converters for Inspect, HELM, lm-eval |
| Cloud storage | S3 or Azure | Not stated |
| Uptake signal | Richest de facto format | 285 PyPI downloads last month |
Table 8. Open judge and guard models
| Model | Maintainer | Licence | Signal | Note |
|---|---|---|---|---|
| Granite Guardian 4.1 8B[161][161] Granite Guardian 4.1 8B model card IBM Primary | IBM | Apache-2.0 | 10k downloads in 30 days | Custom criteria, groundedness, function-call checks |
| Qwen3Guard[162][162] Qwen3Guard models Hugging Face API Primary | Alibaba | Apache-2.0 | 223k downloads (0.6B size) | Safety in 119 languages |
| Llama Guard 4 12B[163][163] Llama Guard 4 model card Meta Primary | Meta | Llama 4 Community License | 88k downloads | MLCommons hazard taxonomy |
Table 9. Which tools ship which statistics
| Tool | Single-run intervals | Judge agreement | Sequential / early stopping | Paired test | Item-response model | Non-inferiority margin | Drift over time |
|---|---|---|---|---|---|---|---|
| Inspect AI | Yes: stderr, bootstrap, Wilson, clustered | Yes: Krippendorff's alpha | Yes | No | n/a | No | No |
| MLflow 3.18 | Yes: bootstrap | n/a | n/a | Yes: McNemar, Wilcoxon | n/a | No | No |
| NeMo Evaluator | Yes: via scipy | n/a | n/a | No | n/a | No | No |
| Epoch AI ECI | n/a | n/a | n/a | n/a | Yes: Bayesian IRT | No | No |
| Typical CI gate (most app eval tools) | No: pass rate vs threshold | No | No | No | No | No | No |
Table 10. GitHub API, 5 Nov 2026.
| Project | Maintainer | Licence | Stars | Status | Role |
|---|---|---|---|---|---|
| E2B[156][156] E2B GitHub Primary | E2B | Apache-2.0 | 14,721 | Very active | Cloud sandboxes for agents |
| gVisor[157][157] gVisor GitHub Primary | Apache-2.0 | 19,875 | Active | Strong container isolation | |
| Modal client[158][158] Modal client GitHub Primary | Modal | Apache-2.0 (client only) | 533 | Active | Serverless sandboxes, closed platform |
| Daytona[159][159] Daytona GitHub Primary | Daytona | not reported by the API | 71,377 | Last push 24 Jul 2026 | Cloud sandboxes for agents |
Table 11. 2026 deals that touched open eval projects.
| Date | Target | Buyer | Effect on the open project |
|---|---|---|---|
| 16 Jan 2026 | Langfuse[168][168] Langfuse acquisition ClickHouse Vendor | ClickHouse | Core stays MIT, cloud continues |
| 3 Mar 2026 | Helicone[169][169] Helicone acquisition Mintlify Vendor | Mintlify | Hosted product in maintenance mode |
| 9 Mar 2026 (now closed) | promptfoo[73][73] Joining OpenAI promptfoo Vendor | OpenAI | Stays open source under MIT[74][74] promptfoo README Primary |
| Mar 2026 | Traceloop (OpenLLMetry)[170][170] Joining ServiceNow Traceloop Vendor | ServiceNow | OpenLLMetry stays open, joins AI Control Tower |
| 22 May 2026 (close) | Galileo[171][171] Galileo acquisition Cisco Vendor | Cisco | Becomes Splunk Agent Observability |
| 29 May 2026 (close) | Portkey[172][172] Portkey acquisition Palo Alto Networks Vendor | Palo Alto Networks | Becomes the AI gateway of Prisma AIRS |
| 1 Oct 2026 (close) | Arize (Phoenix)[173][173] Arize acquisition Dynatrace Vendor | Dynatrace | Phoenix and AX continue, reported $915M[174][174] Dynatrace and Arize ITPro Secondary[175][175] Dynatrace completes Arize deal engineering.com Secondary |
Table 12. Licence models across the eval stack.
| Licence model | Projects | What you can do |
|---|---|---|
| Permissive (MIT, Apache-2.0, BSD) | Inspect, lm-evaluation-harness, Harbor, promptfoo, DeepEval, DeepTeam, Opik, MLflow, garak, PyRIT, verifiers, OpenEnv, tau2-bench, Giskard, Scenario | Use, change, embed and host as a service |
Open core with closed ee/ folder | Langfuse, Agenta, LangWatch | Use the MIT or Apache core freely, but license the enterprise parts |
| Source-available (Elastic License 2.0) | Phoenix server and phoenix-evals | Use internally, but do not offer it as a hosted service |
| Fair-code | Kiln desktop app | Read the terms before commercial use |
| Open SDK, closed platform | LangSmith, Braintrust, Weave server, Modal | Use the SDK, but the back end stays a paid product |
| Licence in transition | MCP, from MIT to Apache-2.0 | Expect more permissive terms |
Table 13. Standard today, still open
| Area | Standard today | Still open |
|---|---|---|
| Model benchmarks | Inspect and lm-evaluation-harness | Funding for leaderboards and static benchmarks |
| Agent tasks | Harbor folder with Dockerfile and test script | Cost and speed of large container runs |
| Environment API | OpenEnv reset, step, state | Size and quality of shared hubs |
| Sandboxes | Docker images | Isolation standards and vendor choice |
| Tool access | MCP | Final licence and versioning |
| Trace transport | OpenTelemetry OTLP | None |
| Trace vocabulary | OpenInference in practice | OTel GenAI conventions still "Development" |
| Eval results on traces | gen_ai.evaluation.result event | Judge, rubric and interval metadata |
| Result exchange | Inspect .eval logs in practice | Every Eval Ever uptake |
| Judges | LLM judges in every framework | Human agreement data for agent transcripts |
| Statistics | Threshold gates and single-run intervals | Paired tests, non-inferiority and drift over time |
| Red team | promptfoo, garak, PyRIT | Neutrality of lab-owned tools |
184 sources, numbered as cited in the report.
- [1] swebench downloads, pypistats. It gives the monthly PyPI download count for SWE-bench. Primary pypistats.org
- [2]
- [3]
- [4]
- [5]
- [6]
- [7]
- [8] Harbor, GitHub API. It gives stars, licence and the move from laude-institute. Primary api.github.com
- [9]
- [10]
- [11]
- [12]
- [13]
- [14]
- [15]
- [16]
- [17]
- [18]
- [19]
- [20]
- [21]
- [22] Inspect docs folder, UK AISI. It covers tasks, scorers, agents, the agent bridge and MCP tools. Primary github.com
- [23] Meridian Labs repos, GitHub search. It lists the Inspect add-ons and Petri projects. Primary github.com
- [24] inspect_evals README. It names Generality Labs as maintainer and sets contributor rules. Primary github.com
- [25]
- [26] NeMo Evaluator README, NVIDIA. It lists interceptors, confidence intervals and Inspect export. Primary github.com
- [27]
- [28] Eval Results, Hugging Face Hub docs. It defines a verified result as an Inspect run in HF Jobs. Primary huggingface.co
- [29] Inspect metrics docs, UK AISI. It lists the error, interval and agreement metrics. Primary github.com
- [30] lm-evaluation-harness README, EleutherAI. It covers YAML tasks, plugins, backends and named users. Primary github.com
- [31] Harbor README. It describes agents, cloud providers and the Terminal-Bench 2.0 role. Primary github.com
- [32]
- [33]
- [34]
- [35]
- [36]
- [37]
- [38] Capabilities Index package, Epoch AI. It describes the Bayesian item-response fit. Primary github.com
- [39]
- [40] Maintenance mode policy, HELM. It explains what the team still maintains. Primary crfm-helm.readthedocs.io
- [41]
- [42]
- [43] HAL harness README, Princeton PLI. It states that the repo stays archived for reference. Primary github.com
- [44] End of the Open LLM Leaderboard, Hugging Face. It announces the retirement on 13 March 2025. Primary huggingface.co
- [45] Leaderboards docs, Hugging Face. It describes the Open LLM Leaderboard in the past tense. Primary huggingface.co
- [46]
- [47]
- [48]
- [49]
- [50]
- [51]
- [52]
- [53]
- [54]
- [55]
- [56]
- [57]
- [58]
- [59]
- [60]
- [61]
- [62]
- [63]
- [64]
- [65]
- [66]
- [67]
- [68]
- [69]
- [70]
- [71]
- [72]
- [73]
- [74] promptfoo README. It states that Promptfoo now belongs to OpenAI and stays MIT-licensed. Primary github.com
- [75]
- [76]
- [77]
- [78]
- [79]
- [80]
- [81] Braintrust Series B, SiliconANGLE. It reports the $80M round, as a secondary source. Secondary siliconangle.com
- [82]
- [83]
- [84]
- [85]
- [86] Comparing evaluation runs, MLflow. It describes the paired tests between two runs. Primary github.com
- [87]
- [88]
- [89] Weave self-managed docs, CoreWeave. It describes Weave on ClickHouse under CoreWeave. Primary docs.coreweave.com
- [90]
- [91]
- [92]
- [93]
- [94]
- [95]
- [96]
- [97]
- [98]
- [99]
- [100]
- [101] appworld downloads, pypistats. It gives a monthly count that likely includes CI pulls. Primary pypistats.org
- [102]
- [103]
- [104]
- [105] inspect_petri, GitHub API. It gives stars, licence and the move from safety-research. Primary api.github.com
- [106]
- [107] verifiers README, Prime Intellect. It describes the library and its links to the Hub. Primary github.com
- [108] verifiers overview, Prime Intellect. It defines tasksets, harnesses, agents and toolsets. Primary github.com
- [109]
- [110] Post on X, Prime Intellect. It claims over 400 crowdsourced environments in October 2025. Single source threadreaderapp.com
- [111] tau2-bench README, Sierra. It describes version 2.0, languages, voice and task counts. Primary github.com
- [112]
- [113]
- [114]
- [115]
- [116] ControlArena repository. It describes the AI control library from UK AISI and Redwood. Primary github.com
- [117]
- [118]
- [119]
- [120]
- [121]
- [122]
- [123]
- [124]
- [125] Red-team configuration, promptfoo. It describes remote and local attack generation. Primary github.com
- [126] garak README, NVIDIA. It describes probes, detectors, harnesses and the REST generator. Primary github.com
- [127]
- [128]
- [129]
- [130]
- [131]
- [132]
- [133]
- [134] OWASP AI Testing Guide. It gives a method for testing the trustworthiness of AI systems. Primary owasp.org
- [135] Top 10 for Agentic Applications for 2026, OWASP. It lists the main security risks of agentic applications. Primary genai.owasp.org
- [136] OTel GenAI conventions, GitHub API. It gives the creation date, stars and licence. Primary api.github.com
- [137]
- [138] OpenInference conventions downloads, pypistats. It gives the monthly PyPI download count. Primary pypistats.org
- [139]
- [140]
- [141] Core GenAI README, OpenTelemetry. It states that the GenAI conventions moved to a new repo. Primary github.com
- [142]
- [143]
- [144]
- [145]
- [146]
- [147]
- [148]
- [149] Inspect eval logs docs, UK AISI. It describes the .eval format and storage options. Primary github.com
- [150] Every Eval Ever README, EvalEval. It describes the schema, the database and the converters. Primary github.com
- [151] every-eval-ever downloads, pypistats. It gives the monthly PyPI download count. Primary pypistats.org
- [152]
- [153]
- [154]
- [155]
- [156]
- [157]
- [158]
- [159]
- [160]
- [161] Granite Guardian 4.1 8B model card, IBM. It gives criteria, scores and the licence. Primary huggingface.co
- [162]
- [163]
- [164] Judge ensembling paper, Composo. It measures the gain from criteria and ensembles. Primary arxiv.org
- [165] Inspect early stopping docs, UK AISI. It describes early stopping and optional stopping. Primary github.com
- [166]
- [167]
- [168] Langfuse acquisition, ClickHouse. It announces the deal and the licence pledge. Vendor clickhouse.com
- [169]
- [170] Joining ServiceNow, Traceloop. It announces the deal and the open-source pledge. Vendor traceloop.com
- [171]
- [172]
- [173]
- [174]
- [175] Dynatrace completes Arize deal, engineering.com. It reports the close on 1 October 2026. Secondary engineering.com
- [176]
- [177]
- [178]
- [179]
- [180] Check Point and Deepchecks, Security Boulevard. It reports the purchase of the Deepchecks team and IP. Secondary securityboulevard.com
- [181]
- [182] Beacon Software and Haize Labs, Osler. It describes the deal and the new research group. Secondary osler.com
- [183]
- [184] Deepchecks price, Dealroom citing Calcalist. It estimates the price at up to $20M. Estimate dealroom.co