Skip to content
verify mcp Beta VerifyMCP is currently in beta. If you notice any issues, get in touch and we’ll put it right.

MCP Slack

PYPI · MCP-SLACK-CRUNCHTOOLS · SCANNED SEP 20

Secure read-only MCP server for Slack workspaces

0 this week 80 Trust /100
Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →

Supply Chain Security100
  • No malware found by supply-chain analysis.Pass
  • No known CVEs affecting this package version or its production dependencies.Pass
  • Runs hatchling.build at install time, a recognised native-build step with no shell scripting around it. View diagnostics → Pass
  • 1 of 23 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency35
  • Source repository is publicly reachable at the declared URL. View diagnostics → Pass
  • Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
  • License check failed: the license (GNU Affero General Public License v3 or later (AGPLv3+)) isn't a recognized OSI-approved license. See how to fix → Fail
  • Actively maintained (last published 178 days ago).Pass
  • Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability76
  • AI-judged instruction clarity (good).Pass
  • Tool/resource definitions use about 1164 tokens (~77/item across 15 items; 15 tools + 0 resources), lean.Pass
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management80
  • Stability observed for 24 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 15 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 16 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a current MCP spec version (2026-07-28).Pass
Install

How do I install the MCP Slack server?

MCP Slack runs locally as a PyPI package, launched with uvx mcp-slack-crunchtools. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

pypi · mcp-slack-crunchtools

# add to Claude Code
claude mcp add crunchtools-slack -- uvx mcp-slack-crunchtools
// .cursor/mcp.json
{
  "mcpServers": {
    "crunchtools-slack": {
      "command": "uvx",
      "args": [
        "mcp-slack-crunchtools"
      ]
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "crunchtools-slack": {
      "command": "uvx",
      "args": [
        "mcp-slack-crunchtools"
      ]
    }
  }
}
# add to Codex CLI
codex mcp add crunchtools-slack -- uvx mcp-slack-crunchtools
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "crunchtools-slack": {
      "type": "local",
      "command": [
        "uvx",
        "mcp-slack-crunchtools"
      ],
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add crunchtools-slack --command uvx --arg mcp-slack-crunchtools
# ~/.hermes/config.yaml
mcp_servers:
  crunchtools-slack:
    command: "uvx"
    args: ["mcp-slack-crunchtools"]
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "crunchtools-slack": {
      "Transport": "stdio",
      "Command": "uvx",
      "Arguments": [
        "mcp-slack-crunchtools"
      ]
    }
  }
}
# add to Vellum
assistant mcp add crunchtools-slack -t stdio -c uvx -a mcp-slack-crunchtools
// mcp.json
{
  "mcpServers": {
    "crunchtools-slack": {
      "command": "uvx",
      "args": [
        "mcp-slack-crunchtools"
      ]
    }
  }
}
Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 20 Sept 26 −3
    • Stability: pass → 0.80 functional
  • 19 Sept 26 +1
    • Stability: 0.97 → pass security
  • 17 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.

  • 15 Sept 26 +16
    • Malware scan: unverified → pass security
  • 14 Sept 26 −15
    • Malware scan: pass → unverified security
  • 13 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 77 to 80. That category is still filling its 30-day observation window: 23 days of observed history at the previous scan, 24 at this one. The score rises as the window fills, whether or not the server changes.

  • 12 Sept 26 −4
    • Stability: pass → 0.77 functional
  • 11 Sept 26 +1
    • Stability: 0.97 → pass security
Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 20 Sept 2026 · Analysed pypi/mcp-slack-crunchtools@0.1.2

Provenance No attestation

The registry publishes no build provenance for this version, so there is nothing to verify.

Result No attestation
Ecosystem pypi

Background: How many MCP packages publish verified provenance →

Install scripts 1 script
Hook Tier Command
build_backend allowlisted hatchling.build

Background: Why install scripts are a supply-chain risk →

Dependencies 23 packages
Packages resolved 23
Stale 1
Tree resolution Complete

Background: SBOMs and build attestations, explained →

MCP tools · 15 exposed · ~1,151 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
slack_auth_test ~47

Test Slack authentication and get info about the token owner. Returns the authenticated user's ID, team ID, team name, username, and workspace URL. Use this to verify the connection is working.

Input schema present but exposes no named parameters.

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_channel_history ~114

Get message history from a Slack channel.

NameTypeReqDescription
channel_idstringyesChannel ID (starts with C, D, or G)
cursorPagination cursor from previous response
inclusivebooleanInclude messages at oldest/latest boundary
latestOnly messages before this timestamp
limitintegerMax messages to return, 1-1000 (default: 100)
oldestOnly messages after this timestamp (e.g., 1234567890.123456)

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_channel_info ~37

Get detailed information about a Slack channel.

NameTypeReqDescription
channel_idstringyesChannel ID (starts with C, D, or G)

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_file_info ~67

Get metadata about a Slack file (no content download).

NameTypeReqDescription
countintegerNumber of comments per page (default: 100)
file_idstringyesFile ID (starts with F)
pageintegerPage of comments (default: 1)

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_reactions ~75

Get reactions for a specific Slack message.

NameTypeReqDescription
channel_idstringyesChannel ID (starts with C, D, or G)
fullbooleanIf true, return complete reaction list for each emoji
timestampstringyesMessage timestamp (e.g., 1234567890.123456)

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_thread_replies ~116

Get replies in a Slack message thread.

NameTypeReqDescription
channel_idstringyesChannel ID (starts with C, D, or G)
cursorPagination cursor from previous response
inclusivebooleanInclude messages at oldest/latest boundary
latestOnly replies before this timestamp
limitintegerMax replies to return, 1-1000 (default: 100)
oldestOnly replies after this timestamp
thread_tsstringyesTimestamp of the parent message

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_user_info ~36

Get information about a Slack user.

NameTypeReqDescription
user_idstringyesUser ID (starts with U, W, or B)

Structured output declared, but exposes no named fields.

No examples provided.

slack_get_user_profile ~49

Get a Slack user's profile information.

NameTypeReqDescription
include_labelsbooleanInclude custom profile field labels
user_idstringyesUser ID (starts with U, W, or B)

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_channel_members ~68

List members of a Slack channel.

NameTypeReqDescription
channel_idstringyesChannel ID (starts with C, D, or G)
cursorPagination cursor from previous response
limitintegerMax members to return, 1-1000 (default: 200)

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_channels ~88

List channels in the Slack workspace.

NameTypeReqDescription
cursorPagination cursor from previous response
exclude_archivedbooleanExclude archived channels (default: true)
limitintegerMax results per page, 1-1000 (default: 200)
typesstringComma-separated channel types: public_channel, private_channel, mpim, im

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_files ~133

List files in the Slack workspace (metadata only, no content download).

NameTypeReqDescription
channel_idFilter by channel ID
countintegerResults per page, 1-100 (default: 100)
pageintegerPage number (default: 1)
ts_fromFilter files created after this Unix timestamp
ts_toFilter files created before this Unix timestamp
typesFilter by types (comma-separated: spaces, snippets, images, gdocs, zips, pdfs, all)
user_idFilter by uploader's user ID

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_reactions ~82

List reactions made by a user.

NameTypeReqDescription
countintegerResults per page, 1-100 (default: 100)
fullbooleanIf true, return complete reaction list
pageintegerPage number (default: 1)
user_idUser ID to list reactions for (default: authenticated user)

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_stars ~62

List starred items for the authenticated user.

NameTypeReqDescription
countintegerResults per page, 1-100 (default: 100)
cursorPagination cursor from previous response
pageintegerPage number (default: 1)

Structured output declared, but exposes no named fields.

No examples provided.

slack_list_users ~48

List users in the Slack workspace.

NameTypeReqDescription
cursorPagination cursor from previous response
limitintegerMax users to return, 1-1000 (default: 200)

Structured output declared, but exposes no named fields.

No examples provided.

slack_search_messages ~129

Search messages in the Slack workspace. Supports Slack search modifiers: from:user, in:channel, has:link, before:date, after:date, during:month.

NameTypeReqDescription
countintegerResults per page, 1-100 (default: 20)
pageintegerPage number (default: 1)
querystringyesSearch query string
sortstringSort by "timestamp" or "score" (default: timestamp)
sort_dirstringSort direction "asc" or "desc" (default: desc)

Structured output declared, but exposes no named fields.

No examples provided.

Common questions

What is the MCP Slack server?

MCP Slack is listed in the public MCP registry as io.github.crunchtools/slack. Secure read-only MCP server for Slack workspaces. This page covers its PyPI package (mcp-slack-crunchtools).

Is the MCP Slack server safe to use?

MCP Slack scores 80 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 20 September 2026. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the MCP Slack server expose?

MCP Slack exposes 15 tools: slack_auth_test, slack_list_channels, slack_get_channel_info, slack_get_channel_history, slack_get_thread_replies, and 10 more. Their descriptions and schemas cost roughly 1,151 tokens of context every time the server is loaded.

Is the MCP Slack server still maintained?

MCP Slack is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.