Sinch Docs MCP Server

What is Sinch Docs MCP Server?

Sinch Docs MCP Server is Sinch's official documentation MCP server, hosted at developers.sinch.com/mcp, that lets AI coding assistants search the Sinch docs and read its API definitions to write integration code. It needs no API key and never calls Sinch APIs itself.

Sinch is a communications platform with APIs for SMS, WhatsApp, RCS and other channels through the Conversation API, plus voice calling, phone numbers, verification, number lookup, fax and SIP trunking. Sinch documents the MCP server on the "AI best practices" page of each API, alongside its llms.txt index and Markdown versions of every page.

How to use Sinch Docs MCP Server?

There is nothing to install. Add this URL to any MCP client that supports remote Streamable HTTP servers:

https://developers.sinch.com/mcp

Our probe connected without credentials. Sinch's guide notes that some clients may show a login prompt; in that case complete it, but no Sinch API key is involved.

Claude Code

Sinch documents this command; pick any server name:

claude mcp add --transport http sinch-docs https://developers.sinch.com/mcp

Then type /mcp in Claude Code to confirm the server and its tools are listed.

Claude Desktop and claude.ai

Open Settings > Connectors, choose Add custom connector, name it "Sinch Docs" and paste https://developers.sinch.com/mcp.

Cursor

Open the command palette, run "Open MCP settings", choose "Add custom MCP" and add the configuration from Sinch's guide:

{
  "mcpServers": {
    "sinch-mcp": {
      "url": "https://developers.sinch.com/mcp"
    }
  }
}

VS Code

Run "MCP: Add Server" from the command palette, select "HTTP", enter the URL and a name. Or add it to .vscode/mcp.json:

{
  "servers": {
    "sinch-docs": {
      "type": "http",
      "url": "https://developers.sinch.com/mcp"
    }
  }
}

Key features of Sinch Docs MCP Server

• Official server documented by Sinch; free and keyless.
• Documentation only: Sinch states it will not call the endpoints it finds. You add the generated code to your project with your own credentials.
• Search across the whole Sinch developer documentation, including its code samples.
• Structured access to more than twenty OpenAPI definitions, including the Conversation API, Voice API and Voice API v2, Numbers, Number Lookup, Verification, Fax, Elastic SIP Trunk, Provisioning, 10DLC registration, Access Keys and Subprojects.
• Endpoint lookups return parameters, examples, security requirements and server URLs.
• Pairs with Sinch's published agent skills (npx skills add sinch/skills) for extra guidance in coding tools.

Sinch Docs MCP Server tools

Our probe returned two MCP tools that wrap a set of documentation functions:

• describe-tools returns the exact TypeScript signatures of the sandbox functions so the assistant does not guess parameters.
• execute runs JavaScript in a sandbox whose only global is tools, with no network access. Through it the assistant calls:
  • listApis to list the documented APIs, and getEndpoints to list one API's paths and methods.
  • getEndpointInfo for full detail on one endpoint, and getSecuritySchemes for its auth.
  • getFullApiDescription for a complete OpenAPI document.
  • search to find relevant documentation content.
  • submitFeedback to report a wrong or incomplete page.

Sinch's guide lists these functions as separate tools with hyphenated names (for example list-apis and get-endpoint-info). The live server currently exposes them through execute, so expect to see only the two tools above in your client.

Use cases of Sinch Docs MCP Server

• Sending a message: "Using the Sinch docs, write a Node.js call to the Conversation API that sends an SMS."
• Voice: "Which Voice API endpoint starts an outbound call, and what parameters does it take?"
• Verification: "Show me how to start an SMS verification with the Verification API."
• Numbers: "List the Numbers API endpoints for searching and activating a phone number."
• US compliance: "What are the steps to register a 10DLC brand and campaign?"

Troubleshooting Sinch Docs MCP Server

• A tool call fails with an unknown function: ask the assistant to run describe-tools first and use the exact names it returns.
• The answer is based on an old API version: several definitions share a title (for example Number Lookup v1 and v2). Ask for the specific version, or pass the filePath that listApis returns.
• The generated code fails against Sinch: the server only reads docs. Check your project's credentials and region, then review the code against the documentation, as Sinch advises.