cli

Syrin CLI is a lightweight MCP tooling suite designed to inspect, validate, and test MCP servers. It provides a set of commands to enumerate tools, statically analyze contracts, run contract tests, and interactively develop against an MCP server. The tool is accessed via the syrin CLI (installed from the npm package @syrin/cli) and can operate against a running MCP server (HTTP/HTTPS) or against local examples. Typical workflows include listing an MCP server’s exposed tools, analyzing tool contracts for issues like ambiguous or underspecified inputs, and running contract tests to ensure guarantees before production.

To use Syrin CLI, install the package (globally or run via npx) and invoke commands such as syrin list, syrin analyse, syrin test, syrin dev, and syrin doctor. Each command targets a specific part of the MCP contract lifecycle: discovery of capabilities, static evaluation of tool contracts, sandboxed execution against contracts, and validation of configuration and connections. When pointing at a server, provide the --transport type (http, https, or stdio) and the URL or script, e.g. --url http://localhost:8000/mcp or --script server.py. The CLI also supports running against local examples or embeddings to validate behavior without a deployed server.

In short, Syrin helps you catch contract issues early—ambiguities, missing tool descriptions, underspecified inputs, and other pitfalls—so your MCP server integrates cleanly with LLMs and avoids runtime surprises.

Prerequisites:

• Node.js >= 20.12.0
• npm >= 9

Option A: Quick start (no installation needed each time)

• Use npx to run the CLI directly without installing:

  npx @syrin/cli analyse --transport http --url https://docs.syrin.dev/mcp

Option B: Install globally for repeated use

1. Install the Syrin CLI globally:

npm install -g @syrin/cli

2. Verify installation:

syrin --version

Option C: Install in a project (local to your repo)

1. Initialize a project (optional but recommended):

npm init -y

2. Install the package locally:

npm install @syrin/cli

3. Run via npx or via an npm script, e.g.:

npx syrin analyse --transport http --url http://localhost:8000/mcp

What to run:

• Analyze your MCP server: syrin analyse --transport http --url <server-url>/mcp
• List tools and resources: syrin list --transport http --url <server-url>/mcp
• Run contract tests: syrin test --transport http --url <server-url>/mcp
• Interactive development/sessions: syrin dev --exec --transport http --url http://localhost:8000/mcp

Tips and notes:

• Ensure your MCP server is reachable from the environment where you run Syrin CLI (consider networking and firewalls when using HTTP URLs).
• For local servers, you can point Syrin to a --script or start a local http server that serves the MCP adapter at /mcp.
• The tool set assumes your MCP server exposes tool contracts in a structured format; use syrin doctor to validate config and connections.
• When using CI, leverage syrin analyse --ci and syrin test --ci --strict to automate contract validation.
• If you encounter issues with missing descriptions or ambiguous tool definitions, pinpoint the offending tools via syrin list or syrin analyse and adjust your tool contracts accordingly.