Slack MCP not_allowed_token_type on conversations_unreads

Slack MCP notallowedtokentype on conversationsunreads

TL;DR: conversationsunreads needs a user token (xoxc or xoxd); a bot token (xoxb) is rejected with notallowedtokentype. Add a user token to the server config alongside the bot token. Restart the client and retry the unread query.

The error

not_allowed_token_type

Fix it

1. Check which token type your Slack MCP config uses.

Expected: It uses a bot token (xoxb).

1. Generate a user token (xoxc or xoxd) for the same Slack app with the needed scopes.

Expected: You have the user token value.

1. Add the user token to the server config env.

Expected: Both tokens are configured.

1. Restart the client and call conversations_unreads.

Expected: It returns unread data.

When this applies

Slack MCP conversationsunreads fails with notallowedtokentype while other tools work on a bot token.

When this does NOT apply

If everything fails, the bot token itself is wrong. missing_scope means the scope is absent, not the token type.

Tool compatibility

korotovsky/slack-mcp-server, recent versions

Also seen as

• Slack MCP unreads token type
• conversations_unreads xoxb fails
• notallowedtoken_type slack MCP

Why it happens

Slack restricts some read APIs to user tokens. The MCP server passes your bot token through, and Slack rejects the token type before even checking scopes.

Edge cases

• User tokens act as you; only request the scopes you need.
• Some workspaces restrict user token creation; ask an admin.
• Keep both tokens in the config; other tools still use the bot token.