Borrowing it
Nothing to install: this file belongs to ccf/agentcairn. 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/ccf/agentcairn/main/CLAUDE.mdgit clone --depth 1 https://github.com/ccf/agentcairnWrote 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/ccf/agentcairn/claude-md)<a href="https://agentmods.dev/instructions/ccf/agentcairn/claude-md"><img src="https://agentmods.dev/badge/instructions/ccf/agentcairn/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.
<a href="https://agentmods.dev/instructions/ccf/agentcairn/claude-md"><img src="https://agentmods.dev/badge/instructions/ccf/agentcairn/claude-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 | $0.01890 | $0.01890 |
| Opus 5.5 | $0.00756 | $0.00756 |
| Sonnet 5.5 | $0.00378 | $0.00378 |
| Haiku 4.5 | $0.00189 | $0.00189 |
Grade C, and why
agentcairn CLAUDE.md scanned grade C with 2 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 2mo 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.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
**Plugins:** agentcairn ships a **Claude Code plugin**, a **Codex plugin**, and an **Antigravity plugin** — all three reuse the same `using-agentcairn-memory` skill and bundled MCP server. The Codex plugin is discoverabl Unrestricted tool accessmediumExcessive agency
A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.
- Run any command: `uv run <cmd>` (e.g. `uv run pytest`, `uv run cairn --help`) How it starts
The opening of the file, as written. The whole thing — 58 lines — stays where its author put it; the contents beside it link to each section on GitHub.
agentcairn — project guide for Claude Code
What this is: a local-first agent-memory system. An Obsidian Markdown vault is the source of truth; a rebuildable embedded DuckDB index provides hybrid retrieval. Daemonless: a cairn CLI + an on-demand READ_ONLY MCP server. Capture is via out-of-band transcript ingestion + an agent remember tool — not live hooks.
Status (2026-06-13): Shipped and on PyPI — current 0.10.1. The full loop is implemented
(cairn.vault/index/embed/search/ingest/mcp + CLI + Claude Code plugin). Specs live in docs/specs/
(the original is 2026-06-08-agentcairn-design.md; later ones cover the config file, the Layer-B LLM
judge, antecedent resolution, and memory consolidation). Releases follow the cut-a-release ritual
(CHANGELOG → tag → Trusted-Publishing → GitHub Release).
Plugins: agentcairn ships a Claude Code plugin, a Codex plugin, and an Antigravity plugin — all three reuse the same using-agentcairn-memory skill and bundled MCP server. The Codex plugin is discoverable via the Codex plugin marketplace; the Antigravity plugin installs from a local directory (agy plugin install takes a dir or a registered marketplace, not a git repo — so cairn install antigravity --source <plugin dir>). cairn install routes by host kind: for plugin hosts (claude-code, codex, antigravity) it installs the plugin by shelling to the host's own CLI; for MCP hosts (cursor, claude-desktop, vscode, gemini) it writes the MCP server config. The Antigravity plugin bundles the MCP server + skill; cairn install antigravity (via agy plugin install) also migrates away any stale mcpServers.agentcairn entry from ~/.gemini/config/mcp_config.json. Gemini, Cursor, and the other MCP hosts do not have plugins. Cursor is the exception among MCP hosts: it has no plugin system, but cairn install cursor ALSO installs the using-agentcairn-memory skill (alongside writing ~/.cursor/mcp.json) via Cursor's Host.skill_dir (~/.cursor/skills), writing ~/.cursor/skills/using-agentcairn-memory/SKILL.md — so any future host exposing a skill_dir can ship the memory skill the same way without being a plugin host.
Capture pipeline (ingest): transcripts from Claude Code, Codex, Antigravity CLI (~/.gemini/antigravity-cli/brain/<uuid>/.system_generated/logs/transcript.jsonl), and Cursor (<CursorUser>/globalStorage/state.vscdb, SQLite cursorDiskKV) are ingested automatically
(auto-detected via a HarnessAdapter seam; cairn sweep picks up whichever harnesses are present). Gemini CLI transcript ingestion is not supported (Google is sunsetting Gemini CLI in favour of Antigravity CLI).
Then: redact → structural candidate selection (authored user turns only) →
judge (embedding/LLM tier; durability + optional distillation) → gate → distill → consolidate
(semantic dedup + supersession, LLM-tier, fail-safe) → write. Redaction-before-write is mandatory;
the judged cache is version-stamped (_JUDGE_CACHE_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.
- 2mo ago First seen · 58 lines · 1,890 tokens per session scan C c6e8755edeee
agentcairn CLAUDE.md is an instructions file published in the GitHub repository ccf/agentcairn (69 stars, last pushed today), licensed Apache-2.0. It adds 1,890 tokens to every session, about $0.0076 per session on Opus 5.5. A static security scan graded it C with 2 findings (reads agent configuration directories, unrestricted tool access). 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.