Borrowing it
Nothing to install: this file belongs to harness/harness-evals. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/harness/harness-evals/main/AGENTS.mdgit clone --depth 1 https://github.com/harness/harness-evalsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/harness/harness-evals/agents-md)<a href="https://agentmods.dev/instructions/harness/harness-evals/agents-md"><img src="https://agentmods.dev/badge/instructions/harness/harness-evals/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/harness/harness-evals/agents-md"><img src="https://agentmods.dev/badge/instructions/harness/harness-evals/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.08079 | $0.08079 |
| Opus 5.5 | $0.03232 | $0.03232 |
| Sonnet 5.5 | $0.01616 | $0.01616 |
| Haiku 4.5 | $0.00808 | $0.00808 |
Grade A, and why
harness-evals AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 637 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md - harness-evals
Project Overview
harness-evals is an open-source AI evaluation framework for LLM agents, prompts, and structured outputs. It provides a pip install-able scoring engine with 70+ metrics across deterministic, structural, operational, reliability, predictability, MCP, similarity, LLM-judged, RAG, grounding, safety, agent, conversation, and security categories.
Core principle: Every applicable metric produces a Score. A metric may return None to skip a case; skipped results are excluded from aggregation, not converted to failed or zero scores. Every metric is a single class with a measure() method.
Data flow: Golden (authored) + agent output -> EvalCase (evaluated) -> Score (result)
Language: Python 3.10+
License: Apache 2.0
Package name: harness-evals
Import name: harness_evals
Build System
pip install -e "." # Core only (deterministic metrics, no LLM key needed)
pip install -e ".[llm]" # + OpenAI, Anthropic for LLM-judged metrics
pip install -e ".[otlp]" # + OTLP metrics & traces export
pip install -e ".[langfuse]" # + Langfuse source/sink
pip install -e ".[harness]" # + Harness AI Service LLM provider
pip install -e ".[benchmarks]" # + Academic benchmarks (MMLU, GSM8K, HumanEval, etc.)
pip install -e ".[all]" # Everything
poetry install --all-extras --with dev # Everything + the Poetry dev group
Build tool: Poetry via pyproject.toml (backend: poetry-core)
No compiled extensions — pure Python.
Testing
pytest tests/ -v # All tests
pytest tests/ -v -m unit # Unit tests only
pytest tests/metrics/ -v # Specific directory
pytest tests/test_core.py -v # Specific file
pytest tests/test_core.py::test_evaluate -v # Specific function
pytest tests/ --cov=harness_evals --cov-report=html # With coverage
- Mark tests:
@pytest.mark.unit,@pytest.mark.integration - Test data:
tests/data/
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 8d ago Changed · +73 lines · +985 tokens per session 1215b5faee9c
- 9d ago Changed · +80 lines · +1,056 tokens per session 518c3906ef07
- 1mo ago Changed 777872f3e1d3
- 1mo ago Changed · +6 lines · +105 tokens per session 2ea1cfff9a74
- 2mo ago Changed · +11 tokens per session 91b89a5f1d6e
- 2mo ago First seen · 478 lines · 5,922 tokens per session scan A 1fd9c3a133a7
harness-evals AGENTS.md is an instructions file published in the GitHub repository harness/harness-evals (38 stars, last pushed 3d ago), licensed Apache-2.0. It adds 8,079 tokens to every session, about $0.0323 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
harness-evals AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| harness-evals AGENTS.mdharness/harness-evals | Instructions file | 38 | 3d ago | Apache-2.0 | A | 8,079 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 9,719 | GitHub Copilot |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 5,516 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | today | MIT | A | 7,461 | Codex, OpenCode |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | today | MIT | A | 4,680 | Codex, OpenCode |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 3,093 | GitHub Copilot |
| vscode model-prompts.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 2,022 | GitHub Copilot |