> ## Documentation Index
> Fetch the complete documentation index at: https://mcpjam-mintlify-docs-update-pr-4867-1789023630416.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# MCPJam Docs

> Test, debug, and evaluate MCP servers, MCP apps, and ChatGPT apps across every major AI client.

MCPJam is the open-source testing and evaluations platform for developers shipping **MCP servers, MCP apps, and ChatGPT apps**. Interactively test and debug tools, prompts, resources, and OAuth across 16 client configurations and 170+ LLMs, with every JSON-RPC message visible. Run evals on test cases, track accuracy over time, and gate regressions before they reach production.

<Frame>
  <img className="block dark:hidden" src="https://mintcdn.com/mcpjam-mintlify-docs-update-pr-4867-1789023630416/giyN9Ke6d0__U3SL/images/playground-hero.webp?fit=max&auto=format&n=giyN9Ke6d0__U3SL&q=85&s=de83e6f17783ecd357e35df53b4e54bc" alt="MCPJam Inspector playground comparing one prompt across Claude, ChatGPT, and Copilot" width="1000" data-path="images/playground-hero.webp" />

  <img className="hidden dark:block" src="https://mintcdn.com/mcpjam-mintlify-docs-update-pr-4867-1789023630416/giyN9Ke6d0__U3SL/images/playground-hero-dark.webp?fit=max&auto=format&n=giyN9Ke6d0__U3SL&q=85&s=e5734cfb844d8bec7ff539c5c03bebc5" alt="MCPJam Inspector playground comparing one prompt across Claude, ChatGPT, and Copilot" width="1000" data-path="images/playground-hero-dark.webp" />
</Frame>

## Four ways to get started

Get started by testing with our hosted app, or test locally on your machine.

<CardGroup cols={2}>
  <Card title="Inspector" icon="binoculars" href="/inspector/playground">
    **On your machine.** An IDE-style workspace for MCP development, with STDIO servers, tunneling, skills, and tasks. Tests local servers over STDIO and HTTP.

    ```bash theme={"theme":"css-variables"}
    npx @mcpjam/inspector@latest
    ```

    or [install the desktop app](/installation)
  </Card>

  <Card title="CLI" icon="terminal" href="/cli/overview">
    **In your shell or CI.** Connectivity, OAuth, conformance, and tool runs with JUnit/JSON output. Tests local servers over STDIO (`--command`) and HTTP (`--url`).

    ```bash theme={"theme":"css-variables"}
    npm i -g @mcpjam/cli
    ```
  </Card>

  <Card title="SDK" icon="code" href="/sdk">
    **In your test suite.** Unit tests, e2e tests, and evals in TypeScript with Jest or Vitest. Spawns local STDIO servers or connects over HTTP.

    ```bash theme={"theme":"css-variables"}
    npm install @mcpjam/sdk
    ```
  </Card>

  <Card title="Hosted" icon="globe" href="https://app.mcpjam.com">
    **In your browser.** Open [app.mcpjam.com](https://app.mcpjam.com), click **Add server**, and enter your server's URL. HTTPS only — STDIO and localhost servers need the Inspector.
  </Card>
</CardGroup>

## What you can build

<AccordionGroup>
  <Accordion title="Debug an MCP server end-to-end" icon="bug">
    Connect any HTTP, HTTPS, or STDIO server, watch every JSON-RPC message live in the Playground, and inspect tool input/output, widget state, and CSP activity per call.

    [Open the Playground →](/inspector/playground) · [JSON-RPC logger →](/inspector/playground#json-rpc-logger)
  </Accordion>

  <Accordion title="Build an MCP App or ChatGPT App widget" icon="layout-dashboard">
    The unified widget renderer handles both `_meta.ui.resourceUri` (MCP Apps) and `openai/outputTemplate` (ChatGPT Apps). The `window.openai` shim is always injected, so you can iterate without a real host.

    [First MCP App →](/guides/first-mcp-app) · [First ChatGPT App in React →](/guides/first-chatgpt-app-react)
  </Accordion>

  <Accordion title="Validate OAuth conformance across protocol versions" icon="shield-check">
    Step through every stage of the MCP authorization flow against protocol versions 03-26, 06-18, 11-25, and 2026-07-28 (Latest), with DCR, pre-registration, and CIMD coverage.

    [Guided OAuth →](/inspector/guided-oauth) · [CLI OAuth conformance →](/cli/oauth-conformance)
  </Accordion>

  <Accordion title="Run evals across LLMs and gate CI on regressions" icon="flask-conical">
    Author cases with expected tool calls, optional expected outputs, and deterministic checks. Run across Claude, GPT, Gemini, and your own providers — or move the same suite into Jest/Vitest with `@mcpjam/sdk`.

    [Evaluate in Inspector →](/inspector/evals) · [Run evals from the SDK →](/sdk/concepts/running-evals) · [CI integration →](/cli/ci)
  </Accordion>

  <Accordion title="Auto-launch Inspector from your dev workflow" icon="code">
    Launch the Inspector with a prefilled server URL, bearer token, and starting tab via CLI flags — wire it into your dev script or a framework integration.

    [Launch from code →](/inspector/launch-from-code)
  </Accordion>

  <Accordion title="Share a server with your team" icon="users">
    In the hosted app, share a server URL the same way you'd share a Google Doc. Teammates connect with one click and pick up where you left off.

    [Hosted overview →](/hosted/overview)
  </Accordion>
</AccordionGroup>

## Capabilities at a glance

| Capability           | Description                                                                                                                                                                                                                                                   |
| -------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Playground           | IDE-style workspace combining chat, manual tool calls, widget rendering, Chat/Trace/Raw views, and multi-model and multi-host compare. OpenAI Apps SDK and MCP App UIs, text tools, Chrome DevTools-style widget emulator. [Read more](/inspector/playground) |
| OAuth Debugger       | Guided MCP OAuth conformance checks: protocol versions 03-26, 06-18, 11-25, 2026-07-28 (Latest); DCR, client pre-registration, CIMD. [Read more](/inspector/guided-oauth)                                                                                     |
| MCP Server Debugging | Manually run tools, resources, templates, and elicitation; full JSON-RPC logs.                                                                                                                                                                                |
| Skills               | Skills in the Playground, read from your local filesystem or from a project. [Read more](/inspector/skills)                                                                                                                                                   |
| Projects             | Shared server groups with real-time team sync. [Read more](/inspector/projects)                                                                                                                                                                               |
| Evals                | Test cases with expected tool calls, run across LLMs, metrics. [Read more](/inspector/evals)                                                                                                                                                                  |
| CLI                  | Run MCPJam checks, probes, and evals from the terminal. Perfect for local dev loops and CI. [Read more](/cli/overview)                                                                                                                                        |
| SDK                  | Programmatic access to MCPJam for custom tooling, scripting, and integrations. [Read more](/sdk)                                                                                                                                                              |
| CI/CD                | Run MCPJam checks and evals in GitHub Actions and other CI systems to gate PRs on regressions. [Read more](/cli/ci)                                                                                                                                           |

## Get help

<CardGroup cols={3}>
  <Card title="Discord" icon="discord" href="https://discord.gg/JEnDtz8X6z">
    Ask the team and the community.
  </Card>

  <Card title="GitHub" icon="github" href="https://github.com/MCPJam/inspector">
    File an issue or open a PR.
  </Card>

  <Card title="Changelog" icon="newspaper" href="/changelog/overview">
    What shipped, and when.
  </Card>
</CardGroup>