Borrowing it
Nothing to install: this file belongs to 2389-research/slack-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/2389-research/slack-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/2389-research/slack-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/2389-research/slack-mcp/claude-md)<a href="https://agentmods.dev/instructions/2389-research/slack-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/2389-research/slack-mcp/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.
<a href="https://agentmods.dev/instructions/2389-research/slack-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/2389-research/slack-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00579 | $0.00579 |
| Opus 5 | $0.00290 | $0.00290 |
| Sonnet 5 | $0.00116 | $0.00116 |
| Haiku 4.5 | $0.00058 | $0.00058 |
Grade A, and why
slack-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 8d 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 — 74 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Slack MCP Server
Overview
MCP server that provides Slack workspace integration. Use when you need to share content with a team, create channels for collaboration, or post messages programmatically.
Available Tools
| Tool | Description |
|---|---|
slack_create_channel |
Create a public or private channel |
slack_invite_to_channel |
Add users to a channel by email or ID |
slack_post_message |
Post a message (markdown supported) |
slack_post_thread |
Reply in a thread |
slack_pin_message |
Pin a message to a channel |
slack_list_users |
List workspace users for ID lookup |
Common Workflows
Create a GTM Review Channel
When user says "push to slack" after generating materials:
1. slack_create_channel(name: "gtm-[product]", is_private: true, description: "GTM review for [product]")
2. slack_invite_to_channel(channel_id: "...", users: ["[email protected]", "[email protected]"])
3. slack_post_message(channel_id: "...", text: "## GTM Materials: [Product]\n\n...")
4. slack_pin_message(channel_id: "...", message_ts: "...")
5. slack_post_message(channel_id: "...", text: "## Email\n\n...")
6. slack_post_message(channel_id: "...", text: "## Blog Post\n\n...")
7. slack_post_message(channel_id: "...", text: "## Tweet Thread\n\n...")
Post Updates to Existing Channel
1. slack_post_message(channel_id: "...", text: "Updated draft:\n\n...")
Discuss in Thread
1. slack_post_thread(channel_id: "...", thread_ts: "...", text: "What about this angle?")
Message Formatting
Slack uses its own markdown variant:
*bold*for bold_italic_for italic`code`for inline code-
>for quotes•for bullet points
2389 Default Users
When creating GTM review channels, always invite:
[email protected](Harper Reed)[email protected](Dylan Richard)
Error Handling
Common errors:
channel_not_found- Channel ID is invalidalready_in_channel- User already in channel (not a failure)user_not_found- Email not found in workspacenot_in_channel- Bot not in channel (needs to be invited first)
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.
- 8d ago First seen · 74 lines · 579 tokens per session scan A 6ea01ab52fbc
slack-mcp CLAUDE.md is an instructions file published in the GitHub repository 2389-research/slack-mcp (1 stars, last pushed 2mo ago), licensed MIT. It adds 579 tokens to every session, about $0.0029 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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