What is github-advisory-mcp AGENTS.md?

Repository instructions for an MCP server that provides GitHub Security Advisories from a local copy of the advisory database. MCP is a way for software tools to expose functions that an AI agent can call.

Use them when developing, building, or bootstrapping the advisory database for this security service.

They explain the required software, setup, build process, and data source needed to run or change the server.

How microsoft/github-advisory-mcp configures Codex and OpenCode

About the project

Microsoft GitHub Advisory MCP Server is an MCP server that queries GitHub Security Advisories from a locally cloned advisory database. It helps coding agents find advisories, list them, and retrieve specific records. The catalogue entries operate this server through its MCP tools.

microsoft/github-advisory-mcp · 9 stars · on GitHub

Reuse

Borrowing it

Nothing to install: this file belongs to microsoft/github-advisory-mcp. 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/microsoft/github-advisory-mcp/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/microsoft/github-advisory-mcp

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/microsoft/github-advisory-mcp/agents-md/github.svg)](https://agentmods.dev/instructions/microsoft/github-advisory-mcp/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/microsoft/github-advisory-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/microsoft/github-advisory-mcp/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/microsoft/github-advisory-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/microsoft/github-advisory-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 1,159 This file is loaded in full into every session.

When invoked 1,159 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.

Model	Per session	Once invoked
Fable 5.1	$0.01159	$0.01159
Opus 5.5	$0.00464	$0.00464
Sonnet 5.5	$0.00232	$0.00232
Haiku 4.5	$0.00116	$0.00116

Measured 1mo ago against content hash fb2e1d6d2466, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

github-advisory-mcp 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.

AGENTS.md · 118 lines

How it starts

The opening of the file, as written. The whole thing — 118 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Guidance for AI coding agents (and humans) working in this repository. Keep changes minimal, typed, and covered by tests. For contribution policy see CONTRIBUTING.md; for user-facing docs see README.md.

What this is

An MCP server that serves GitHub Security Advisories from a local clone of github/advisory-database. Two-tier design: MCP server (stdio or HTTP) → local Express REST API → LocalRepositoryDataSource (reads advisory JSON from disk).

Core MCP tools: list_advisories, get_advisory (full parameters in the README).

Prerequisites

Node.js 20+ (CI runs 20.x and 22.x)
Git
The server runs from dist/ — rebuild after every source change.

Build

npm install      # or: npm ci  (installs from package-lock.json)
npm run build    # tsc -> dist/

Bootstrap the advisory database (needed to run/serve)

The server reads advisory JSON from ADVISORY_REPO_PATH (default ./external/advisory-database). Clone it once:

./scripts/setup-advisory-database.sh
# or manually:
git clone --depth=1 https://github.com/github/advisory-database.git external/advisory-database

external/ is git-ignored. If absent, the server also auto-clones on first tool call.

Run

stdio (what .vscode/mcp.json launches — for VS Code / agent use):

ADVISORY_REPO_PATH=./external/advisory-database node dist/index.js

HTTP streaming:

MCP_PORT=18006 ADVISORY_API_PORT=18005 \
ADVISORY_REPO_PATH=./external/advisory-database node dist/http-server.js
# health: http://localhost:18006/health

Test

Unit (fast, hermetic — start here): npx vitest run test/unit
E2E (spawns the server; needs the advisory DB): npm run test:e2e
- The first list_advisories cold-builds an in-memory index over the whole DB; if it flakes on the default 30s timeout, raise it: npx vitest run test/e2e --testTimeout=120000.
Integration (Azure OpenAI): npm run test:integration — requires Azure credentials; skip unless you're specifically exercising the AI SDK path.
npm test runs all suites (including integration). Prefer test/unit for routine work.

Read the full file on GitHub · 118 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.

1mo ago First seen · 118 lines · 1,159 tokens per session scan A fb2e1d6d2466

Subscribe to this mod's changes

github-advisory-mcp AGENTS.md is an instructions file published in the GitHub repository microsoft/github-advisory-mcp (9 stars, last pushed 2d ago), licensed MIT. It adds 1,159 tokens to every session, about $0.0046 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 2026-09-15.

Backend and APIs CVE Security TypeScript advisories mcp model-context-protocol

github-advisory-mcp AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
github-advisory-mcp AGENTS.mdmicrosoft/github-advisory-mcp	Instructions file	9	2d ago	MIT	A	1,159	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

github-advisory-mcp: Instructions file for Codex