refs: Instructions file for Claude Code

CLAUDE.md

refs CLAUDE.md is an instructions file for Claude Code from kaisers-io/refs. It costs 1,338 tokens per session, scanned B, original, MIT.

Repository-specific instructions for working on the refs project, including testing and pull-request checks.

In plain words
What is it for?
Use it when making changes to the refs repository, especially when validating a build, testing against a real repository, and checking generated commands.
Why use it?
It records the project's expectations so an AI coding agent can follow its required build, integration, and review process. The supplied text does not describe a general-purpose add-on.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions Claude Code; mentions AGENTS.md; mentions Codex.

This is kaisers-io/refs's own configuration. It tells Claude Code how to work on refs itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything refs configures →

Reuse

Borrowing it

Nothing to install: this file belongs to kaisers-io/refs. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/kaisers-io/refs/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/kaisers-io/refs

Made for: Claude Code.

Wrote 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.

agentmods badge for refs CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/kaisers-io/refs/claude-md/github.svg)](https://agentmods.dev/instructions/kaisers-io/refs/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/kaisers-io/refs/claude-md"><img src="https://agentmods.dev/badge/instructions/kaisers-io/refs/claude-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.

agentmods 80×15 button for refs CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/kaisers-io/refs/claude-md"><img src="https://agentmods.dev/badge/instructions/kaisers-io/refs/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 1,338 This file is loaded in full into every session.
When invoked 1,338 The same file — it is already loaded in full.
Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.01338 $0.01338
Opus 5 $0.00669 $0.00669
Sonnet 5 $0.00268 $0.00268
Haiku 4.5 $0.00134 $0.00134

Measured yesterday against content hash 9121dd00fabb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade B, and why

refs CLAUDE.md scanned grade B with 1 finding 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 yesterday.

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.

Unrestricted tool accessmediumExcessive agency

A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.

5. Run any command refs printed **verbatim** — the string it printed, not an argv you rebuilt from
CLAUDE.md · 99 lines

How it starts

The opening of the file, as written. The whole thing — 99 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Working in this repository

AGENTS.md is a symlink to this file, so Claude Code and Codex read the same instructions.

Finish every PR with a real test

pnpm check passing is not evidence the feature works. Fixtures carry the shapes their author thought of; real repositories carry the ones nobody did. Before marking a PR ready:

  1. pnpm build — test the bundle at packages/cli/bin/refs.mjs, not the TypeScript source.
  2. Clone a real upstream repository from GitHub into a scratch directory.
  3. Drive the feature end to end against it with a scratch REFS_HOME, using the same --json path an agent uses.
  4. Compare what refs reports against ground truth computed from git itself — e.g. package names from git ls-tree at both revisions, diffed. Report the comparison, not just the output.
  5. Run any command refs printed verbatim — the string it printed, not an argv you rebuilt from the same parts. A suggested command that does not execute is a bug, and rebuilding the argv hides exactly the bugs that matter: a <ref> placeholder passes straight through a hand-built array while a shell reads it as an input redirection.
  6. Exercise the lifecycle: remove, then confirm nothing is left (config, state, checkout, pruned parent directories, no orphans in doctor, resolve answers unmatched_query), then add again and confirm behaviour is unchanged.

To put a ref at a chosen point in history without fabricating anything, clone the real repository, git checkout -B main <old-sha> in it, refs add from that file:// path with REFS_ALLOW_FILE_URLS=1 so refs builds the config from real state, then advance the clone and refs sync. The range is then real upstream history.

Why this is a rule: a feature once shipped with 988 green tests, including end-to-end ones against file:// fixtures, and reported nothing at all on TanStack Query — two negation patterns in its pnpm-workspace.yaml silenced every finding. No fixture used a negation pattern.

Read the full file on GitHub · 99 lines

Changes

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.

  1. yesterday First seen · 99 lines · 1,338 tokens per session scan B 9121dd00fabb

Subscribe to this mod's changes

refs CLAUDE.md is an instructions file published in the GitHub repository kaisers-io/refs (7 stars, last pushed 2d ago), licensed MIT. It adds 1,338 tokens to every session, about $0.0067 per session on Opus 5. A static security scan graded it B with 1 finding (unrestricted tool access). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-09.

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