inspector/clients/cli/README.md
Bob Dickinson 2488ca5e38
feat: port CLI, TUI, and launcher from v1.5 into v2 (#1452)
Ports the CLI, TUI, and launcher from v1.5 into v2 behind a single
`mcp-inspector` entrypoint (launcher → web/cli/tui). Includes the
`mcp-inspector --web --dev` launcher fix (Vite alias resolution + prod-server
double-start), the root `postinstall` install cascade with simplified CI, and
spec/AGENTS docs (no-workspaces rationale, Development setup).

Closes #1246.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 20:27:49 -04:00

4.2 KiB

MCP Inspector CLI Client

The CLI mode enables programmatic interaction with MCP servers from the command line. It is ideal for scripting, automation, continuous integration, and establishing an efficient feedback loop with AI coding assistants.

Running the CLI

You can run the CLI client directly via npx:

npx @modelcontextprotocol/inspector --cli node build/index.js

The CLI mode supports operations across tools, resources, and prompts, returning structured JSON output.

Examples

Basic usage

npx @modelcontextprotocol/inspector --cli node build/index.js

With a configuration file

npx @modelcontextprotocol/inspector --cli --config path/to/config.json --server myserver

List available tools

npx @modelcontextprotocol/inspector --cli node build/index.js --method tools/list

Call a specific tool

npx @modelcontextprotocol/inspector --cli node build/index.js --method tools/call --tool-name mytool --tool-arg key=value --tool-arg another=value2

Call a tool with JSON arguments

npx @modelcontextprotocol/inspector --cli node build/index.js --method tools/call --tool-name mytool --tool-arg 'options={"format": "json", "max_tokens": 100}'

List available resources

npx @modelcontextprotocol/inspector --cli node build/index.js --method resources/list

List available prompts

npx @modelcontextprotocol/inspector --cli node build/index.js --method prompts/list

Remote Servers

You can also connect to remote MCP servers using HTTP or SSE transports.

Connect to a remote MCP server (default is SSE)

npx @modelcontextprotocol/inspector --cli https://my-mcp-server.example.com

Connect with Streamable HTTP transport

npx @modelcontextprotocol/inspector --cli https://my-mcp-server.example.com --transport http --method tools/list

Pass custom headers

npx @modelcontextprotocol/inspector --cli https://my-mcp-server.example.com --transport http --method tools/list --header "X-API-Key: your-api-key"

Options

MCP server (which server to connect to)

Options that specify the MCP server (config file, ad-hoc command/URL, env vars, headers) are shared by the Web, CLI, and TUI and are documented in MCP server configuration: --config, --server, -e, --cwd, --header, --transport, --server-url, and the positional [target...].

CLI-specific (what to invoke)

Option Description
--method <method> MCP method to invoke (e.g. tools/list, tools/call, resources/list, prompts/list).
--tool-name <name> Tool name (for tools/call).
--tool-arg <key=value> Tool argument; repeat for multiple. Use key='{"json":true}' for JSON.
--uri <uri> Resource URI (for resources/read).
--prompt-name <name> Prompt name (for prompts/get).
--prompt-args <key=value> Prompt arguments; repeat for multiple.
--log-level <level> Logging level for logging/setLevel (e.g. debug, info).
--metadata <key=value> General metadata (key=value); applied to all methods.
--tool-metadata <key=value> Tool-specific metadata for tools/call.

Why use the CLI?

While the Web Client provides a rich visual interface, the CLI is designed for:

  • Automation: Ideal for CI/CD pipelines and batch processing.
  • AI Coding Assistants: Provides a direct, machine-readable interface (JSON) for tools like Cursor or Claude to verify changes immediately.
  • Log Analysis: Easier integration with command-line utilities (like jq) to process and analyze MCP server output.