<MCP.Playground/>
online

MCP Inspector Online

FreeNo npx

The MCP Inspector, online. Connect to any remote MCP server straight from the browser — inspect tools, prompts and resources, view raw JSON-RPC frames, and call tools with custom arguments. No npx, no Node install, no local config.

Beyond inspection — drive with AI

Watch Claude, GPT and Gemini call your tools in a live conversation. Compare model behavior side-by-side.

Test with AI →Browse templates

✦ Free credits on sign-up · no credit card

Loading MCP Inspector…

MCP weekly digest

New servers, security advisories, and tutorials — straight to your inbox. No spam.

Online MCP Inspector — what it does

The MCP Inspector is the canonical debugging tool for Model Context Protocol servers — it lists capabilities, calls tools, and shows raw protocol frames. Anthropic ships a local version you launch with npx @modelcontextprotocol/inspector. This online MCP Inspector does the same job for remote servers, in your browser, with no Node install.

Paste a server URL and it runs the standard initialize handshake, fetches tools/list, prompts/list and resources/list, and renders each entry with its full JSON schema.

Inspector vs the local npx tool

Inspector Online (this page)npx @modelcontextprotocol/inspector
Install requiredNoneNode 18+ & npm
Remote (HTTP / SSE)✓✓
Streamable HTTP✓✓
STDIO (local child process)✗ (browser cannot spawn)✓
Raw JSON-RPC log✓✓
Test with real LLMAgent StudioManual only

Rule of thumb: use this online inspector for anything reachable over the network, and the local npx tool when you are developing a STDIO server on your machine.

What you can inspect

  • Server info — name, version, capabilities advertised in initialize
  • Tools — name, description, full inputSchema, and tools/call response
  • Prompts — argument list and rendered output for any prompt template
  • Resources — URIs, MIME types, and the raw content of resources/read
  • JSON-RPC frames — every request and response in chronological order
  • Errors — protocol-level errors with the original code, message and data

Frequently Asked Questions

Is this the same as the Anthropic MCP Inspector?
It performs the same role — capability discovery, tool/prompt/resource calls, raw JSON-RPC — but runs entirely in the browser instead of as a local Node app. For remote servers you do not need to install anything.
Can the online inspector connect to a STDIO server?
No — browsers cannot spawn local child processes. For STDIO servers use the local npx @modelcontextprotocol/inspector tool. Most production MCP servers expose an HTTP or SSE endpoint, which this online inspector handles directly.
Does it support Streamable HTTP?
Yes. Both the original HTTP + SSE transport and the newer Streamable HTTP transport from the 2025 spec are supported. The inspector auto-detects which transport the server speaks during the initialize handshake.
Can I share an inspection result with a teammate?
Use the export button in the JSON-RPC log to download the full session as JSON. Paste it into a GitHub issue or share over Slack — your teammate sees every frame.
Does it work with authenticated servers?
Yes. Add a Bearer token in the auth field — the inspector sends it on every JSON-RPC call and surfaces 401 errors verbatim in the log.

Related tools

MCP Inspector Online — Browser-Based Alternative to npx @modelcontextprotocol/inspector | MCP Playground