MCP Server Inspector for VS Code

Inspect and debug Model Context Protocol servers without leaving the editor.

• MCP Inspector view in the activity bar with a Create New Connection button
• Connect over STDIO, SSE or Streamable HTTP
• Edit every header (Authorization, API keys, tenant headers, …) and environment variable, and enable or disable each one without deleting it
• A connection is only added after it connects successfully. It then appears in the sidebar under the name you gave it.
• Every tool, prompt, resource and resource template the server offers is listed under the connection
• Search them by name, title or URI, and sort them by name instead of the server's order
• Click an item to see its details (description, annotations, input/output schema) and run it, or use the ▶ button next to it to run it straight away with the last arguments:
  • a form generated from the JSON Schema: nested objects, arrays with add / remove / reorder, and oneOf / anyOf variants picked by their discriminator (e.g. "type": "click")
  • or a JSON editor with syntax highlighting, completion of property names, values and whole variant templates from the schema (Ctrl+Space), hover documentation and schema validation
  • progress notifications, cancellation, duration
  • text, images, audio, embedded resources, resource links and structuredContent; JSON is shown in a read-only editor with folding
  • the raw result with Copy / Open in Editor
• Lists refresh automatically when the server sends list_changed notifications
• Every JSON-RPC message, server log and stderr line is written to the MCP Inspector output channel
• Connection errors show the underlying cause (refused connections, malformed HTTP responses, the server's stderr) instead of a bare "fetch failed"

Installation

Search for MCP Server Inspector in the Extensions view (VS Code uses the Visual Studio Marketplace; VSCodium, Cursor, Windsurf and other editors use Open VSX), or download the .vsix from the latest release and install it:

code --install-extension vsc-mcp-inspector-<version>.vsix

Or use Extensions → ⋯ → Install from VSIX….

Usage

1. Open the MCP Inspector view in the activity bar.
2. Click Create New Connection.
3. Enter a name and choose a transport:
   • STDIO – command (npx, node, uvx, docker, …), arguments, working directory and environment variables. Pasting a full command line such as npx -y @modelcontextprotocol/server-everything into Command splits it into command and arguments.
   • SSE – the SSE endpoint URL (usually …/sse) plus headers.
   • Streamable HTTP – the MCP endpoint URL (usually …/mcp) plus headers.
4. Click Test Connection to check the server, or Connect & Save to add it.
5. Expand the connection and click a tool to open it. Fill in the parameters and press Run Tool (Ctrl+Enter).

Right-click a connection to connect, disconnect, reconnect, edit, delete it or show server info.

Searching and sorting

Click Search (magnifier) in the view's title bar and type: the tree only shows the tools, prompts, resources and templates whose name, title or URI contains the text, with the groups expanded and the number of matches next to each group. The filter stays when the input closes; Clear Search in the title bar shows everything again.

Items are listed in the order the server returns them. Change Sort Order in the title bar sorts them by name, A → Z or Z → A; the choice is saved in the mcpInspector.sortOrder setting.

Reading a tool result

A tool call returns a CallToolResult with these parts, shown separately:

• content – blocks meant for the model: text, image, audio, embedded resource and resource_link.
• structuredContent – a JSON object for programs, validated against the tool's outputSchema. The MCP spec asks tools that return it to also put the same JSON in a text block for older clients; when the two match, the text block is collapsed as "same JSON as structuredContent".
• Raw result – the whole result object of the JSON-RPC response exactly as received (including isError and _meta), useful for debugging the server. Long strings such as base64 images are shortened in the view; Copy and Open in Editor keep them intact.

Variables

Header values, environment values, arguments, the command, the working directory and the URL can use:

For example, set the header Authorization to Bearer ${env:MY_API_TOKEN} so the token never gets stored.

Where connections are stored

Connection settings are kept in VS Code's global state. Header and environment variable values are stored in VS Code's SecretStorage (the OS keychain), not in settings files.

Settings

Feedback

Found a bug or have an idea? Open an issue on GitHub.