Borrowing it
Nothing to install: this file belongs to harness/harness-ai. 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-ai/main/AGENTS.mdgit clone --depth 1 https://github.com/harness/harness-aiWrote 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-ai/agents-md)<a href="https://agentmods.dev/instructions/harness/harness-ai/agents-md"><img src="https://agentmods.dev/badge/instructions/harness/harness-ai/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-ai/agents-md"><img src="https://agentmods.dev/badge/instructions/harness/harness-ai/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 | $0.02689 | $0.02689 |
| Opus 5.5 | $0.01076 | $0.01076 |
| Sonnet 5.5 | $0.00538 | $0.00538 |
| Haiku 4.5 | $0.00269 | $0.00269 |
Grade A, and why
harness-ai 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 1mo 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 — 171 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Contribution guide for AI coding agents working in this repository. Follows the agents.md specification. Human contributors should treat it as the canonical reference alongside README.md.
Claude Code reads CLAUDE.md, which is a symlink to this file.
Gemini CLI reads GEMINI.md inside extensions/gemini/.
Cursor / Copilot / Codex / Aider read this file directly.
Project overview
harness-ai is a distribution monorepo that packages Harness AI integrations — skills, governance hooks, workspace rules, MCP config — as separate plugins/extensions for each major AI coding environment (Cursor, Claude Code, VS Code + Copilot, Gemini CLI). The Cursor plugin is published to the Cursor Marketplace; the others mirror the same skills surface for their respective platforms.
Dev environment
# Required — Node 22+ for validator scripts (ESM)
node --version # expect v22.x
# Clone and orient
git clone https://github.com/harness/harness-ai
cd harness-ai
# Skills mirror (upstream — edits happen there, not here)
git clone https://github.com/harness/harness-skills ../harness-skills
No npm install at repo root. Hook scripts under plugins/cursor/scripts/ run with Node stdlib only (no dependencies).
Build & test commands
File-scoped validators — run the closest one to what you changed.
# Everything (VS Code + Claude + Gemini + Cursor)
./scripts/validate.sh
# Cursor plugin deep check (manifest, mcp.json, hooks, frontmatter, skill-dir match)
( cd plugins/cursor && node scripts/validate-plugin.mjs )
# A single hook script — syntax only
node --check plugins/cursor/scripts/check-templates.mjs
# Smoke-test a hook fail-open path (should print {"permission":"allow"})
echo '{"tool_name":"MCP:harness_create","tool_input":{"resource_type":"pipeline","body":{}}}' \
| env -u HARNESS_API_KEY -u HARNESS_ACCOUNT_ID ./plugins/cursor/scripts/check-templates.mjs
# Skills drift from upstream — must produce no diff after sync
./scripts/sync-skills.sh ../harness-skills
git diff --stat plugins/*/skills/
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.
- 1mo ago First seen · 171 lines · 2,689 tokens per session scan A e3a620d7fadf
harness-ai AGENTS.md is an instructions file published in the GitHub repository harness/harness-ai (27 stars, last pushed 4d ago), licensed Apache-2.0. It adds 2,689 tokens to every session, about $0.0108 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.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.