Claude · MCP testing

Connect your MCP server to Claude.

Getting a server to connect is the easy half; knowing Claude then uses it correctly is the rest. MCPJam takes the same config you already have and runs it against Claude's behavior, driven by anthropic/claude-haiku-4.5, locally, in about two minutes.

Terminal
npx @mcpjam/inspector@latest

Connecting to Claude

Your existing config

MCPJam takes the same server object you'd put in an mcp.json file. No Claude-specific rewrite to test it.

Connection defaults

Claude connections default to a 10s request timeout. A tool slower than that fails here even if it passes locally.

Platform

Claude runs on web with pointer input. MCPJam emulates that context.

Emulation model

Tests run against anthropic/claude-haiku-4.5, the model MCPJam uses to emulate Claude.

Then verify behavior

A successful connection isn't a working integration. Run a real prompt through the Playground and watch what Claude does with your tools.

How we know

Assumed: Inferred defaults, not yet verified against the client. Last reviewed 2026-07-08.

Walkthrough: Claude

Run npx @mcpjam/inspector@latest, connect the MCP server config you already use, and select Claude as the host. MCPJam emulates Claude with anthropic/claude-haiku-4.5 on web, so what you see is this host's behavior, not a generic client's.

Confirm the server initializes and its tools list, then run a real prompt through the Playground. If a tool takes longer than 10s, it fails here. The trace shows exactly where the time went.

Frequently asked questions

Run npx @mcpjam/inspector@latest, connect your server, and select Claude. MCPJam emulates the host with anthropic/claude-haiku-4.5, so you can watch the real behavior locally, free and open source.

Claude connections default to 10 seconds. A tool that takes longer fails in this host even if it works in local tests. (Catalog last reviewed 2026-07-08.)

MCPJam's host-compat catalog (the same data behind caniuse.dev). Assumed: Inferred defaults, not yet verified against the client. Last reviewed 2026-07-08.

See it in Claude before your users do.

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

Open source · no credit card · ~2 min

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