--- slug: "inspector" source_type: "readme" source_url: "https://cdn.jsdelivr.net/gh/mcpjam/inspector@main/README.md" repo: "https://github.com/mcpjam/inspector" source_file: "README.md" branch: "main" ---
MCPJam Inspector V1 logo
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MCPJam is the development platform for MCP servers, MCP apps, and ChatGPT apps. - **Debug**: Inspect every JSON-RPC message and OAuth exchange across host configurations with full traces. - **Chat**: Talk to any LLM against your server with full trace visibility into tool calls and context across agent, host app, your server. - **Inspect**: Explore your server’s tools, resources, and prompts in one place. - **Evaluate**: Run evals across multiple LLMs and track accuracy over time so you catch regressions early. - **CLI**: Probe servers, run doctor checks, exercise OAuth flows, and list tools/resources/prompts straight from your terminal. - **SDK**: Programmatically drive inspections, snapshot server capabilities, and assert on tool/resource shapes from your own tests. - **CI/CD**: Wire the CLI and SDK into GitHub Actions (or any pipeline) to run e2e tests, evals, OAuth checks, and spec conformance on every PR. No more ngrok or ChatGPT/Claude subscription needed. MCPJam is the fastest way to iterate on any MCP project. ### πŸš€ Quick Start Open the hosted web app. No install needed. πŸ‘‰ [app.mcpjam.com](https://app.mcpjam.com) Or run MCPJam locally for HTTP/S and local STDIO servers: ```bash npx @mcpjam/inspector@latest ``` MCPJam Inspector Demo # Table of contents - [Installation Guides](#installation-guides) - [Key Features](#key-features) - [App Builder](#app-builder) - [Chat](#chat) - [OAuth Debugger](#oauth-debugger) - [MCP Server Debugging](#mcp-server-debugging) - [Skills](#skills) - [Workspaces](#workspaces) - [Evals](#evals) - [CLI](#cli) - [SDK](#sdk) - [CI/CD](#cicd) - [Contributing](#contributing-) - [Links](#links-) - [Community](#community-) - [Shoutouts](#shoutouts-) - [License](#-license) # Installation Guides MCPJam Inspector runs three ways: a hosted web app, a desktop app for Mac and Windows, or via your terminal. The web app is HTTPS-only and has no install. Terminal and Desktop support HTTP/S and local STDIO servers. ### Requirements [![Node.js](https://img.shields.io/badge/Node.js-20+-green.svg?style=for-the-badge&logo=node.js)](https://nodejs.org/) [![TypeScript](https://img.shields.io/badge/TypeScript-5+-blue.svg?style=for-the-badge&logo=typescript)](https://www.typescriptlang.org/) Node.js 20+ is only required for the terminal install (`npx`). The hosted web app and desktop apps have no local runtime requirements. ## Hosted Web App Open [app.mcpjam.com](https://app.mcpjam.com) in your browser. No install required. Always on the latest version, and you can share MCP server links with teammates the same way you'd share a Google Doc. - HTTPS MCP server URLs only (for HTTP or local STDIO servers, use Desktop or Terminal). - No STDIO, tunneling, skills, or tasks. Those require the local inspector. See [Hosted App docs](https://docs.mcpjam.com/hosted/overview) for details. ## Desktop App Download the installer for your OS. Supports HTTP/S and local STDIO servers. No Node.js required. - [Install Mac](https://github.com/MCPJam/inspector/releases/latest/download/MCPJam.Inspector.dmg) - [Install Windows](https://github.com/MCPJam/inspector/releases/latest/download/MCPJam-Inspector-Setup.exe) ## Terminal Run the inspector via `npx` (supports HTTP/S and local STDIO): ```bash npx @mcpjam/inspector@latest ``` After it starts, open the printed `localhost` URL in your browser. ## Docker Run MCPJam Inspector using Docker, bound to localhost for security: ```bash docker run -p 127.0.0.1:6274:6274 mcpjam/mcp-inspector ``` The app is available at `http://127.0.0.1:6274`. Always use `-p 127.0.0.1:6274:6274` (not `-p 6274:6274`) to keep the inspector local-only. On macOS/Windows, connect to host MCP servers via `http://host.docker.internal:PORT` instead of `127.0.0.1`. # Key features | Capability | Description | | -------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | App Builder | Debug your server against a model: tool calls or in-panel chat, with Chat, Trace, and Raw. OpenAI Apps SDK and MCP app UIs, text tools, Chrome DevTools-style widget emulator. [Read more](https://docs.mcpjam.com/inspector/app-builder) | | Chat | Multi-server chat on frontier models (free). Chat, Trace, Raw; compare up to 3 models. [Read more](https://docs.mcpjam.com/inspector/chat) | | OAuth Debugger | Guided MCP OAuth conformance checks: protocol versions 03-26, 06-18, 11-25; DCR, client pre-registration, CIMD. [Read more](https://docs.mcpjam.com/inspector/guided-oauth) | | MCP Server Debugging | Manually run tools, resources, templates, and elicitation; full JSON-RPC logs. | | Skills | Skills in Chat and App Builder; local filesystem only. [Read more](https://docs.mcpjam.com/inspector/skills) | | Workspaces | Shared server groups with real-time team sync. [Read more](https://docs.mcpjam.com/inspector/workspaces) | | Evals | Test cases with expected tool calls, run across LLMs, metrics. [Read more](https://docs.mcpjam.com/inspector/test-cases) | | CLI | Run MCPJam checks, probes, and evals from the terminal. Perfect for local dev loops and CI. [Read more](https://docs.mcpjam.com/cli/overview) | | SDK | Programmatic access to MCPJam for custom tooling, scripting, and integrations. [Read more](https://docs.mcpjam.com/sdk) | | CI/CD | Run MCPJam checks and evals in GitHub Actions and other CI systems to gate PRs on regressions. [Read more](https://docs.mcpjam.com/cli/ci) | ## App Builder Debug your server against a model using tool calls or in-panel chat, with Chat, Trace, and Raw views. Supports OpenAI Apps SDK and MCP app UIs, text tools, and a Chrome DevTools-style widget emulator to iterate on widgets locally. - Manually invoke a tool to instantly view the widget, or chat with your server using an LLM. - View all JSON-RPC messages and `window.openai` messages in the logs. - Change emulator device to Desktop, Tablet, or Mobile views. - Test your app's locale change, CSP permissions, light / dark mode, hover & touch, and safe area insets. MCPJam App Builder MCPJam App Builder trace view _Trace view: every tool call, agent step, and JSON-RPC message._ ## Chat Multi-server chat on frontier models for free, or bring your own API key. Chat, Trace, and Raw views; compare up to 3 models side-by-side. View your server's token usage. MCPJam Chat comparing frontier models side by side ## OAuth Debugger Guided MCP OAuth conformance checks with step-by-step explanations. Test against every version of the OAuth spec (03-26, 06-18, and 11-25). Support for client pre-registration, Dynamic Client Registration (DCR), and Client ID Metadata Documents (CIMD). MCPJam OAuth Flow Debugger ## MCP Server Debugging MCPJam contains all of the tooling to test your MCP server. Manually run tools, resources, resource templates, prompts, and elicitation flows, with full JSON-RPC observability. MCPJam has all features from the original inspector and more. MCPJam MCP Tools ## Skills Use Skills in Chat and App Builder to extend models with local, reusable behaviors. Local filesystem only. Your data never leaves your machine. [Read more](https://docs.mcpjam.com/inspector/skills) ## Workspaces Group your servers into shared workspaces with real-time team sync, so everyone on your team is testing against the same configuration. [Read more](https://docs.mcpjam.com/inspector/workspaces) ## Evals Define test cases with expected tool calls and run them across multiple LLMs. Track accuracy metrics over time to catch regressions early and improve your server with every iteration. [Read more](https://docs.mcpjam.com/inspector/test-cases) ## CLI Run MCPJam from the terminal for fast local dev loops and CI integration. Probe servers, run OAuth checks, inspect tools and resources, and execute evals without leaving your shell. [Read more](https://docs.mcpjam.com/cli/overview) ## SDK Programmatic access to MCPJam for custom tooling, scripting, and integrations. Build your own workflows on top of MCPJam's inspection and evaluation primitives. [Read more](https://docs.mcpjam.com/sdk) ## CI/CD Wire MCPJam into GitHub Actions, GitLab CI, or your CI system of choice to run conformance, E2E tests, and evals on every PR. Catch MCP server regressions before they ship. [Read more](https://docs.mcpjam.com/cli/ci) # Contributing πŸ‘¨β€πŸ’» We're grateful for you considering contributing to MCPJam. Please read our [contributing guide](https://github.com/mcpjam/inspector/blob/HEAD/CONTRIBUTING.md). Join our [Discord community](https://discord.gg/JEnDtz8X6z) where the contributors hang out at. # Links πŸ”— - [Website](https://www.mcpjam.com/) - [Blog](https://www.mcpjam.com/blog) - [Pricing](https://www.mcpjam.com/pricing) - [Docs](https://docs.mcpjam.com/) # Community 🌍 - [Discord](https://discord.gg/JEnDtz8X6z) - [𝕏 (Twitter)](https://x.com/mcpjams) - [LinkedIn](https://www.linkedin.com/company/mcpjam) --- # License πŸ“„ This project is licensed under the **Apache License 2.0**. See the [LICENSE](https://github.com/mcpjam/inspector/tree/HEAD/LICENSE).