Borrowing it
Nothing to install: this file belongs to fopost/fopost-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.
curl -O https://raw.githubusercontent.com/fopost/fopost-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/fopost/fopost-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/fopost/fopost-mcp/claude-md)<a href="https://agentmods.dev/instructions/fopost/fopost-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/fopost/fopost-mcp/claude-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 5.1 | $0.01879 | $0.01879 |
| Opus 5 | $0.00940 | $0.00940 |
| Sonnet 5 | $0.00376 | $0.00376 |
| Haiku 4.5 | $0.00188 | $0.00188 |
Grade A, and why
fopost-mcp CLAUDE.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 6d 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 — 138 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
Guidance for Claude Code (claude.ai/code) when working in this repository.
What This Is
@fopost/mcp — a Model Context Protocol server that exposes the FoPost REST API as MCP tools, so
any MCP-aware client (Claude Desktop, Cursor, ChatGPT desktop, Continue) can list, schedule, edit,
and publish social posts, inspect account health, and run the AI features. Published on npm and run
with npx -y @fopost/mcp. TypeScript, ESM only, Node >= 18, bin fopost-mcp, MIT.
It does not depend on @fopost/sdk. src/client.ts is a ~90-line fetch wrapper written in
this repo, and the only runtime dependencies are @modelcontextprotocol/sdk, zod, and
zod-to-json-schema. Do not add the SDK "to share code" — the whole point of the hand-rolled
client is that the published tarball stays tiny and has no FoPost dependency to keep in lockstep.
It is still bound by the API contract in fopost-api-collections/openapi.json and breaks when
that contract changes.
Brand Rules
- The product is FoPost (
fopost.com). Never write "OwlStack" — retired Aug 2026. - Never write an email address. Support is https://fopost.com/contact and GitHub issues.
- Never name AI providers/models, infrastructure vendors, or any person. Tool descriptions and error text are user-facing: name the FoPost feature, never the model behind it.
Architecture
src/index.ts stdio server: reads config, builds the tool list, wires ListTools + CallTool
src/client.ts FoPostClient (fetch) + FoPostApiError
src/types.ts ToolDefinition<S> — name, description, Zod inputSchema, typed execute
src/tools/ posts.ts (7 tools), accounts.ts (3), ai.ts (4) — 14 total
src/globals.d.ts declares __PKG_VERSION__, injected by tsup from package.json
Transport is stdio. console.error is the only safe logging channel; anything written to
stdout corrupts the JSON-RPC stream.
Config is environment only, read once at startup in readConfig():
| Variable | Required | Default |
|---|---|---|
FOPOST_API_KEY |
yes, or the process exits 1 | — |
FOPOST_API_URL |
no | https://api.fopost.com |
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.
- 6d ago First seen · 138 lines · 1,879 tokens per session scan A 28ab74d3a00e
fopost-mcp CLAUDE.md is an instructions file published in the GitHub repository fopost/fopost-mcp (0 stars, last pushed 2d ago), licensed MIT. It adds 1,879 tokens to every session, about $0.0094 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 2026-08-31.
Other instructions, from other repositories
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.
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.
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).
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.