Borrowing it
Nothing to install: this file belongs to dcosson/h2. 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/dcosson/h2/main/AGENTS.mdgit clone --depth 1 https://github.com/dcosson/h2Wrote 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/dcosson/h2/agents-md)<a href="https://agentmods.dev/instructions/dcosson/h2/agents-md"><img src="https://agentmods.dev/badge/instructions/dcosson/h2/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/dcosson/h2/agents-md"><img src="https://agentmods.dev/badge/instructions/dcosson/h2/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 | $0.00305 | $0.00305 |
| Opus 5.5 | $0.00122 | $0.00122 |
| Sonnet 5.5 | $0.00061 | $0.00061 |
| Haiku 4.5 | $0.00030 | $0.00030 |
Grade A, and why
h2 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- h2 CLAUDE.md — 100% identical, 0 lines differ
What it actually says
Testing Rules
Never use config.ConfigDir() in tests. Tests must not touch the real h2 config
directory. Use setupFakeHome(t) or a similar pattern that sets H2_DIR to a temp
directory and calls config.ResetResolveCache(). This prevents test side effects on
the real ~/.h2 directory and ensures test isolation.
Release Process
Commit Quality Gate
Before every feature commit, run make check and ensure it passes.
When doing a production release, follow this sequence:
- Ensure you are on the
mainbranch first. - Fetch and fast-forward
maintoorigin/main(git fetch origin main && git pull --ff-only origin main). - Determine the version bump and update the h2 version:
- If unsure what bump to use, ask the user.
- Use semver rules:
patchfor non-breaking changes.- for pre-1.0 versions:
minorfor breaking changes. - for 1.0+ versions:
majorfor breaking changes.
- Update
docs/CHANGELOG.mdwith changes since the last version tag and its tagged commit. - Run all test suites and ensure they pass.
- Run
make checkand ensure it passes. - Run
make build-releaseand ensure it passes. - Tag the current
HEADwith the release version.
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 · 29 lines · 305 tokens per session scan A b66f628862b2
h2 AGENTS.md is an instructions file published in the GitHub repository dcosson/h2 (163 stars, last pushed yesterday), licensed MIT. It adds 305 tokens to every session, about $0.0012 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).
vscode model-prompts.instructions.md
Model-specific prompt authoring and registry guidelines.