langgraph AGENTS.md

A set of instructions for Claude Code in LangGraph, a monorepo where multiple libraries are kept in one repository under separate folders.

In plain words
What is it for?
Use it when changing a LangGraph library, locating the right package, running its Make-based checks, or analyzing a proposed plan with Corridor when that tool is available.
Why use it?
It tells the agent how to handle security analysis and which formatting, linting, and test checks to run for each library before a pull request.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/langchain-ai/langgraph/agents-md
Clone the repo
git clone --depth 1 https://github.com/langchain-ai/langgraph

Made for: Codex, OpenCode.

Per session 477 This file is loaded in full into every session.
When invoked 477 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.00477 $0.00477
Opus 5 $0.00238 $0.00238
Sonnet 5 $0.00095 $0.00095
Haiku 4.5 $0.00048 $0.00048

Measured yesterday against content hash e5a0e5318267, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

langgraph 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 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.

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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

AGENTS.md · 66 lines

How it starts

The opening of the file, as written. The whole thing — 66 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS Instructions

This repository is a monorepo. Each library lives in a subdirectory under libs/.

Corridor security analysis

When Corridor's analyzePlan tool is available, create a plan and use the tool to analyze it before generating or modifying code. Apply the resulting security guidance before writing code.

When you modify code in any library, run the following commands in that library's directory before creating a pull request:

  • make format – run code formatters
  • make lint – run the linter
  • make test – execute the test suite

To run a particular test file or to pass additional pytest options you can specify the TEST variable:

TEST=path/to/test.py make test

Other pytest arguments can also be supplied inside the TEST variable.

Libraries

The repository contains several Python and JavaScript/TypeScript libraries. Below is a high-level overview:

  • checkpoint – base interfaces for LangGraph checkpointers.
  • checkpoint-postgres – Postgres implementation of the checkpoint saver.
  • checkpoint-sqlite – SQLite implementation of the checkpoint saver.
  • cli – official command-line interface for LangGraph.
  • langgraph – core framework for building stateful, multi-actor agents.
  • prebuilt – high-level APIs for creating and running agents and tools.
  • sdk-js – JS/TS SDK for interacting with the LangGraph REST API.
  • sdk-py – Python SDK for the LangGraph Server API.

Dependency map

The diagram below lists downstream libraries for each production dependency as declared in that library's pyproject.toml (or package.json).

checkpoint
├── checkpoint-postgres
├── checkpoint-sqlite
├── prebuilt
└── langgraph

prebuilt
└── langgraph

sdk-py
├── langgraph
└── cli

sdk-js (standalone)

Changes to a library may impact all of its dependents shown above.

  • Do NOT use Sphinx-style double backtick formatting (``code``). Use single backticks (`code`) for inline code references in docstrings and comments.

Read the full file on GitHub · 66 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 · 66 lines · 477 tokens per session scan A e5a0e5318267

Subscribe to this mod's changes

langgraph AGENTS.md is an instructions file published in the GitHub repository langchain-ai/langgraph (40,717 stars, last pushed 2d ago), licensed MIT. It adds 477 tokens to every session, about $0.0024 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.