What is slack-mcp-server CLAUDE.md?

A set of project instructions for developing an MCP server that connects to Slack. It documents the required workflow, technologies, architecture, and Git steps for that specific project.

Use it when working on the referenced Slack MCP server and following its spec-kit development process.

It gives contributors a shared process for planning, implementing, checking, committing, and pushing changes. A monorepo or MCP concepts are not explained by the supplied information.

How Themetralla3000/slack-mcp-server configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to Themetralla3000/slack-mcp-server. 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/Themetralla3000/slack-mcp-server/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/Themetralla3000/slack-mcp-server

Made for: Claude Code.

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/themetralla3000/slack-mcp-server/claude-md/github.svg)](https://agentmods.dev/instructions/themetralla3000/slack-mcp-server/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/themetralla3000/slack-mcp-server/claude-md"><img src="https://agentmods.dev/badge/instructions/themetralla3000/slack-mcp-server/claude-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/themetralla3000/slack-mcp-server/claude-md"><img src="https://agentmods.dev/badge/instructions/themetralla3000/slack-mcp-server/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 567 This file is loaded in full into every session.

When invoked 567 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	$0.00567	$0.00567
Opus 5	$0.00283	$0.00283
Sonnet 5	$0.00113	$0.00113
Haiku 4.5	$0.00057	$0.00057

Measured 9d ago against content hash 8bc05e8b7747, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

slack-mcp-server 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 9d 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.

CLAUDE.md · 39 lines

How it starts

The opening of the file, as written. The whole thing — 39 lines — stays where its author put it; the contents beside it link to each section on GitHub.

mcp-slack — agent instructions

Workflow

This project uses Spec Driven Development via spec-kit. Always read .specify/memory/constitution.md and the current SPEC before writing code.

Available spec-kit commands:

/speckit.specify — generate or update the SPEC
/speckit.plan — generate implementation plan from SPEC
/speckit.implement — implement a task from the plan
/speckit.checklist — verify implementation against SPEC
/speckit.analyze — analyse existing code against SPEC

Commit and push rule

After every completed step: commit AND push. No exceptions. This includes spec-kit artifacts: SPEC files, plans, checklists — everything goes to GitHub. Format: type(scope): description Examples:

docs: add SPEC for mcp-slack
docs: add implementation plan
chore: init typescript project and install dependencies
feat(channels): channels_create, channels_list and channels_invite tools
test(channels): unit tests with mocked WebClient

Push command: git push origin main

Architecture reference

See .specify/memory/constitution.md for the full technical spec, module pattern, tool list and stack requirements.

Active Technologies

TypeScript 5.7, ESM modules, Node.js 22 LTS + @modelcontextprotocol/sdk (MCP server + stdio transport), @slack/web-api (Slack client), zod (schema validation), zod-to-json-schema (MCP inputSchema generation), vitest (tests), dotenv (env loading) (001-slack-mcp-server)
N/A — stateless proxy; all state lives in Slack (001-slack-mcp-server)
TypeScript 5.7, ESM modules, Node.js 22 LTS (unchanged) + @slack/web-api (files.getUploadURLExternal, files.completeUploadExternal), Node.js built-in fs (file reading), Node.js built-in path (filename derivation), Node.js 22 built-in fetch (PUT upload to pre-signed URL) (002-file-upload)
N/A — stateless; files are read from filesystem and forwarded to Slack (002-file-upload)

Recent Changes

001-slack-mcp-server: Added TypeScript 5.7, ESM modules, Node.js 22 LTS + @modelcontextprotocol/sdk (MCP server + stdio transport), @slack/web-api (Slack client), zod (schema validation), zod-to-json-schema (MCP inputSchema generation), vitest (tests), dotenv (env loading)

Read the full file on GitHub · 39 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.

9d ago First seen · 39 lines · 567 tokens per session scan A 8bc05e8b7747

Subscribe to this mod's changes

slack-mcp-server CLAUDE.md is an instructions file published in the GitHub repository Themetralla3000/slack-mcp-server (1 stars, last pushed 2mo ago), licensed MIT. It adds 567 tokens to every session, about $0.0028 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.

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slack-mcp-server: Instructions file for Claude Code