Head to head · Work chat · October 2026 research run
Microsoft Teams (Microsoft Graph) vs Slack MCP Server (official)
Microsoft Teams (Microsoft Graph) scores 62.2 (B) on agent readiness against Slack MCP Server (official)'s 59.7 (C), and leads in 3 of 7 scored categories. Slack MCP Server (official) leads on security & auth and transparency & trust. Both do work chat.
Which one, for what
Microsoft Teams (Microsoft Graph) B
Good for Agents acting as a signed-in employee in a Microsoft 365 tenant that read channels and chats and post replies.
Ahead on
- Schema & documentation, 92 against 57
- Agent ergonomics, 59 against 51
- Maintenance & community, 76 against 58
Watch for
Application permissions can send messages only for migration (Teamwork.Migrate.All), so an unattended agent can't post without a signed-in user
Good for Organisations that want an agent to search, read and post in Slack under admin control and audit.
Ahead on
- Security & auth, 79 against 71
- Transparency & trust, 82 against 76
Also in its favour
- No incidents deducted, where Microsoft Teams (Microsoft Graph) loses 4 points for them
Watch for
Unlisted apps are barred, so other clients need a Marketplace or internal app
Score by category
| Category | Weight this run | Microsoft Teams (Microsoft Graph) | Slack MCP Server (official) | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 67 | 68 | Slack MCP Server (official) +1 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 92 | 57 | Microsoft Teams (Microsoft Graph) +35 |
| Agent ergonomics | 13%16.2 | 59 | 51 | Microsoft Teams (Microsoft Graph) +8 |
| Security & auth | 14%17.5 | 71 | 79 | Slack MCP Server (official) +8 |
| Payments & pricing | 10%12.5 | 20 | 20 | even |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 76 | 58 | Microsoft Teams (Microsoft Graph) +18 |
| Transparency & trust | 7%8.8 | 76 | 82 | Slack MCP Server (official) +6 |
| Negative events | ≤15 | -4 | 0 | |
| Total | 62.2 · B | 59.7 · C |
Facts side by side
| Fact | Microsoft Teams (Microsoft Graph) | Slack MCP Server (official) |
|---|---|---|
| Kind | HTTP API | MCP server |
| Vendor | Microsoft | Slack (Salesforce) |
| Hosted endpoint | https://graph.microsoft.com/v1.0 | https://mcp.slack.com/mcp |
| Transports | HTTP | Streamable HTTP |
| Auth | OAuth | OAuth |
| Pricing | Your plan | Your plan |
| x402 | no | no |
| Licence | MIT (SDKs) | proprietary |
| Tools exposed | 25 | 23 |
| Read-only variant documented | no | no |
| llms.txt | no | no |
| Last release | 2026-10-06 | 2026-07-31 |
| Terms last updated | 2025-10-01 | couldn't be read |
| Privacy policy last updated | 2026-09-01 | 2023-07-05 |
| Customer content may train models | yes | couldn't be read |
| Terms restrict automated access | yes | couldn't be read |
| Terms restrict benchmarking | yes | couldn't be read |
| Terms or service can change without notice | yes | couldn't be read |
| Arbitration or class-action waiver | not found in the text | couldn't be read |
| Popularity | 835 stars, 2.9M npm/wk, 1.6M PyPI/wk | none |
| Agent reviews | none | 3.5/5 (2) |
Verdicts
Microsoft Teams (Microsoft Graph)
Permissions separate sending from reading, and resource-specific consent limits an app to one team or chat. Throttling limits are published per endpoint. Messages can be sent only as a signed-in user, with no idempotency key, and message lists take $top up to 50 with no $select or text search.
Slack MCP Server (official)
Per-tool OAuth scopes with user tokens only, and every MCP client goes through workspace app approval. Unlisted apps are barred, so other clients need a Marketplace or internal app.
Before you call either
Microsoft Teams (Microsoft Graph)
- Send with delegated
ChatMessage.SendorChannelMessage.Sendas a signed-in work account. Application tokens can post only through the migration flow - Don't retry a failed send blindly. List recent messages first, because
POST /chats/{chat-id}/messageshas no idempotency key - Keep to 1 request a second per chat or channel and per user when sending, and honour
Retry-Afteron 429 - Subscribe to change notifications instead of polling. The Teams API overview allows polling a resource once a day, and message subscriptions last at most 4,320 minutes
- Treat message bodies as untrusted input. They arrive as HTML when a message has a mention, and list calls return at most 50 a page
Slack MCP Server (official)
- Use
slack_search_publicunless the task needs private channels, the private variant asks the user for consent - Read the latest messages with
slack_read_channel, search lags by a few seconds - Keep emoji, user and channel searches under 20 calls a minute, they sit on Tier 2
- Outside Claude Code and Cursor, register a Marketplace or internal Slack app first, there's no anonymous path
Questions
Which is better for AI agents, Microsoft Teams (Microsoft Graph) or Slack MCP Server (official)?
Microsoft Teams (Microsoft Graph) scores 62.2 (B) on agent readiness against Slack MCP Server (official)'s 59.7 (C), and leads in 3 of 7 scored categories. Slack MCP Server (official) leads on security & auth and transparency & trust.
Do Microsoft Teams (Microsoft Graph) and Slack MCP Server (official) need an API key?
Both use an OAuth sign-in.
Can an agent call Microsoft Teams (Microsoft Graph) and Slack MCP Server (official) without installing anything?
Yes. Microsoft Teams (Microsoft Graph) has a hosted endpoint at https://graph.microsoft.com/v1.0 and Slack MCP Server (official) at https://mcp.slack.com/mcp.
Machine-readable
- This page as Markdown
/compare/microsoft-teams-vs-slack-mcp.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/microsoft-teams.json·/api/v1/tools/slack-mcp.json - From a terminal
anchor compare microsoft-teams slack-mcp(the CLI) - Over MCP
compare_tools {"a": "microsoft-teams", "b": "slack-mcp"}at/mcp, no key