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.
npx agentmods add instructions/genmcp/gen-mcp/agents-mdgit clone --depth 1 https://github.com/genmcp/gen-mcpWrote 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/genmcp/gen-mcp/agents-md)<a href="https://agentmods.dev/instructions/genmcp/gen-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/genmcp/gen-mcp/agents-md.svg" alt="Measured on agentmods" 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 | $0.00593 | $0.00593 |
| Opus 5 | $0.00296 | $0.00296 |
| Sonnet 5 | $0.00119 | $0.00119 |
| Haiku 4.5 | $0.00059 | $0.00059 |
Grade A, and why
gen-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 5d 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.
How it starts
The opening of the file, as written. The whole thing — 40 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GenMCP Dev Guidance
GenMCP provides a declarative way to create MCP servers around existing systems
The declarative file formats are described in ./docs/mcpfile.md (tool definitions) and ./docs/mcpserver.md (server config)
Some examples can be found in ./examples/
Repository Layout
./pkg/builder: builder to create container images from an MCP file that will contain the mcp server./pkg/cli: cli commands and utilities for thegenmcpcli./pkg/converter: packages to automatically convert different types of applications into an MCP file. Currently, there are subpackages for OpenAPI specs and cli conversion with an agent./pkg/invocation/: core invocation interfaces and utilities. Subpackages for specific invocation types (http, cli)./pkg/mcpfile/: core types for the mcp file./pkg/mcpserver/: core mcp server implementation./pkg/oauth/: OAuth helpers, primarily to be used in./pkg/mcpserver./pkg/observability/: observability packages to be used throughout./cmd/genmcp/: the entry point for the genmcp CLI./cmd/genmcp-server/: the entry point for the genmcp server binary (to be used in containers)./examples/: various examples of how to use genmcp./docs/: docs around the mcp file spec./specs/: generated json schema specs for the mcp file format./test/: integration tests for the project
Dev commands
There are more makefile commands than those listed here, but these are the only ones you need to worry about while developing genmcp
make build: build everything - in general, this is how to build the projectmake update-codegen: this will update the codegen for the json schemas. Call this whenever you make changes to the core typesmake test: this will correctly re-build required binaries and run all the tests
Coding Guidelines
- When adding logs, check whether you are using the server-only logger (embedded in the
MCPServertype, and accessed from invocation contexts withlogging.BaseFromContext(ctx)) or the server and client logger. Make sure that any logs with sensitive info use the server-only logger - When writing unit tests, follow the table test convention used throughout the codebase
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.
- 5d ago First seen · 40 lines · 593 tokens per session scan A 8784fcbc1be6
gen-mcp AGENTS.md is an instructions file published in the GitHub repository genmcp/gen-mcp (44 stars, last pushed 3d ago), licensed Apache-2.0. It adds 593 tokens to every session, about $0.0030 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.
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).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
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 oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.