Create MCP Server

Register an external MCP server without connecting to it. A duplicate URL returns 409; use Update MCP Server to change the existing registration. The server remains disconnected until List MCP Server Tools succeeds.

OAuth scope: api:write.

POST/api/v2/mcp-servers

Authorization

X-API-Key<token>

Your Sim API key, personal or workspace-scoped. Generate one under Settings, then API Keys. Operations that reject workspace keys say so in their own description.

In: header

Request Body

application/json

Configuration for a new MCP server.

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X POST "https://www.sim.ai/api/v2/mcp-servers" \  -H "X-API-Key: YOUR_API_KEY" \  -H "Content-Type: application/json" \  -d '{    "workspaceId": "a91c4b2e-6d3f-4e8a-b5c7-0d9e2f1a8c64",    "name": "Docs server",    "url": "https://mcp.example.com/sse",    "authType": "headers",    "headers": {      "Authorization": "Bearer YOUR_TOKEN"    }  }'
{
  "data": {
    "id": "mcp-3f7a9c21",
    "name": "Docs server",
    "description": "Internal documentation tools",
    "transport": "streamable-http",
    "authType": "headers",
    "url": "https://mcp.example.com/sse",
    "timeout": 30000,
    "retries": 3,
    "enabled": true,
    "connectionStatus": "disconnected",
    "lastError": null,
    "toolCount": 0,
    "createdAt": "2026-06-01T09:14:00.000Z",
    "updatedAt": "2026-06-20T14:02:11.000Z",
    "hasHeaders": true,
    "headerNames": [
      "Authorization"
    ],
    "hasOauthClientSecret": false
  }
}
{
  "error": {
    "code": "BAD_REQUEST",
    "message": "Invalid request"
  }
}
{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "Authentication required"
  }
}
{
  "error": {
    "code": "FORBIDDEN",
    "message": "Insufficient workspace permissions",
    "details": {
      "code": "INSUFFICIENT_WORKSPACE_ROLE"
    }
  }
}
{
  "error": {
    "code": "NOT_FOUND",
    "message": "Not found"
  }
}
{
  "error": {
    "code": "CONFLICT",
    "message": "The request conflicts with the current state of the resource"
  }
}
{
  "error": {
    "code": "PAYLOAD_TOO_LARGE",
    "message": "Request body is too large"
  }
}
{
  "error": {
    "code": "UNSUPPORTED_MEDIA_TYPE",
    "message": "Request body must be sent as application/json"
  }
}
{
  "error": {
    "code": "RATE_LIMITED",
    "message": "API rate limit exceeded",
    "details": {
      "retryAfter": "2026-01-01T00:00:30.000Z"
    }
  }
}
{
  "error": {
    "code": "INTERNAL_ERROR",
    "message": "Internal server error"
  }
}
{
  "error": {
    "code": "SERVICE_UNAVAILABLE",
    "message": "Service temporarily unavailable"
  }
}
GETList WorkspacesPOSTCreate Workflow MCP Server