Building MCP Servers

An MCP server is a Model Context Protocol endpoint that exposes Celigo Tools and builder-mode APIs as callable tools for external AI agents and MCP clients. Concerns when building an MCP server:

• Endpoint identity -- unique relativeURI that forms the server's URL path
• Tool selection -- which Tool resources to expose, each with an MCP-compatible name
• API selection -- which builder-mode API resources to expose (script-mode APIs are not supported)
• Annotations -- MCP-standard behavior hints (readOnlyHint, destructiveHint, idempotentHint, openWorldHint) that help AI agents decide when and how to call a tool
• Overrides -- per-server customization of a tool's connections, exports, imports, and routers without modifying the underlying tool definition
• Name uniqueness -- tool names must be unique across all tools[] and apis[] entries within the server

MCP servers do not have their own authentication mechanism. Incoming MCP requests authenticate via the Celigo API token; outbound calls to external systems use the connections referenced by the underlying tools and APIs.

Used alongside tools and APIs. The MCP server is a thin exposure layer -- all processing logic lives in the referenced Tool and API resources.

Composition Patterns