Slackbot · MCP testing

Test how Slackbot calls your MCP tools.

Slackbot decides which tool to call and what to do with the result. In Slackbot, the model sees none of the images your tools return, in any result shape we track. MCPJam runs your server through Slackbot with openai/gpt-5-nano so you see the real tool calls instead of guessing from a bug report.

Terminal
npx @mcpjam/inspector@latest

How Slackbot handles your tool results

Image results

No image shape reaches the model in Slackbot. If a tool's answer is an image, Slackbot users get nothing useful. Return text or a link instead.

Emulation model

MCPJam drives Slackbot with openai/gpt-5-nano, so tool selection reflects this host, not a generic model.

Extensions

Slackbot advertises io.modelcontextprotocol/ui.

See the call

Trace shows every step from prompt to response with timings. The exact tool, the exact arguments.

Score it

Evals run realistic requests through Slackbot and score whether the right tool was picked with the right arguments.

How we know

Probed: Verified by running against the client. Last reviewed 2026-07-08.

Walkthrough: Slackbot

Run npx @mcpjam/inspector@latest, connect the MCP server config you already use, and select Slackbot as the host. MCPJam emulates Slackbot with openai/gpt-5-nano on web, so what you see is this host's behavior, not a generic client's.

Ask for something in natural language and watch which tool Slackbot picks and with what arguments. Open Trace for the timed step-by-step, then turn the recurring cases into an eval suite so a regression fails the gate instead of your users.

Frequently asked questions

Run npx @mcpjam/inspector@latest, connect your server, and select Slackbot. MCPJam emulates the host with openai/gpt-5-nano, so you can watch the real behavior locally, free and open source.

No. In Slackbot, images returned by MCP tools never reach the model, in any result shape we track. (Catalog last reviewed 2026-07-08.)

MCPJam's host-compat catalog (the same data behind caniuse.dev). Probed: Verified by running against the client. Last reviewed 2026-07-08.

See it in Slackbot before your users do.

One command, your existing server config, Slackbot's real behavior in the loop.

Open source · no credit card · ~2 min

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