claudian: Instructions file for Codex

AGENTS.md

claudian AGENTS.md is an instructions file for Codex, OpenCode from YishenTu/claudian. It costs 2,411 tokens per session, scanned A, original, MIT.

A set of repository instructions describing how coding agents should work in the Claudian project.

In plain words
What is it for?
Use it when changing Claudian, especially code for its chat, collaboration, provider, application, or styling areas.
Why use it?
It gives agents project-specific rules about providers, scoped guides, documentation, and maintaining instruction files.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions CLAUDE.md; mentions subagents; mentions AGENTS.md.

This is YishenTu/claudian's own configuration. It tells Codex and OpenCode how to work on claudian 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 claudian configures →

About the project

Claudian is an Obsidian plugin that embeds AI coding agents in a note vault, allowing them to read, edit, search, and manage files there. It is for users who want to work with agents alongside their notes, using features such as inline editing, plans, reusable prompts, and external tool connections.

YishenTu/claudian · 15,212 stars · on GitHub

Reuse

Borrowing it

Nothing to install: this file belongs to YishenTu/claudian. 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/YishenTu/claudian/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/YishenTu/claudian

Made for: Codex, OpenCode.

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.

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Per session 2,411 This file is loaded in full into every session.
When invoked 2,411 The same file — it is already loaded in full.
Security scan A 0 findings. 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 $0.02411 $0.02411
Opus 5 $0.01205 $0.01205
Sonnet 5 $0.00482 $0.00482
Haiku 4.5 $0.00241 $0.00241

Measured 3d ago against content hash 135505d82362, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

claudian 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 3d 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.

AGENTS.md · 156 lines

How it starts

The opening of the file, as written. The whole thing — 156 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Project

Claudian is an Obsidian plugin that embeds provider-backed coding agents in a sidebar and inline-edit flow. Claude is the default provider. Codex, Grok, OpenCode, and Pi are optional providers that plug into the same conversation model through Conversation.providerId and opaque provider-owned providerState.

Do not assume provider parity. Check each provider's capabilities.ts, registration.ts, and UI config before wiring shared behavior.

Scope Guides

  • Before editing a scoped area, read its nearest scoped guide:
    • src/app/AGENTS.md
    • src/core/AGENTS.md
    • src/features/chat/AGENTS.md
    • src/features/collab/AGENTS.md
    • src/providers/claude/AGENTS.md
    • src/providers/codex/AGENTS.md
    • src/providers/grok/AGENTS.md
    • src/providers/opencode/AGENTS.md
    • src/providers/pi/AGENTS.md
    • src/style/AGENTS.md

AGENTS.md Maintenance

  • AGENTS.md is execution context for agents, not general documentation. Keep only repository- or scope-specific information that a capable agent would not reliably know; every statement must change implementation, review, or verification behavior.
  • Keep repository-wide rules here; put local ownership, dependencies, invariants, failure modes, verification, and active decisions in the narrowest scoped guide that governs them.
  • Do not duplicate inherited guidance or silently contradict it. State a necessary local exception and its rationale explicitly.
  • Omit tours, ordinary implementation details, temporary status, and general engineering advice.
  • Record a decision only when it is active, surprising from the code, expensive to reverse, and reflects a real tradeoff. State the decision, rationale, and any concrete reconsideration condition; use Git history as the archive.
  • CLAUDE.md files should import the nearest AGENTS.md; do not duplicate shared guidance there.

Commands

npm run dev
npm run build
npm run typecheck
npm run lint
npm run lint:fix
npm run test
npm run test:watch
npm run test:coverage

Read the full file on GitHub · 156 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. 3d ago Changed · +2 lines · +70 tokens per session 135505d82362
  2. 6d ago Changed · +5 lines · +109 tokens per session 15362439828b
  3. 9d ago First seen · 149 lines · 2,232 tokens per session scan A b97e02ddfb8c

Subscribe to this mod's changes

claudian AGENTS.md is an instructions file published in the GitHub repository YishenTu/claudian (15,212 stars, last pushed today), licensed MIT. It adds 2,411 tokens to every session, about $0.0121 per session on Opus 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.

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