Read-only MCP support for AI clients

[preston]

Tools building in native agentic support benefit greatly from MCP tools for common operations such as search. HAPI FHIR JPA server's default settings have an MCP endpoint, for example, that is very useful. I would like to have direct support for FHIRsmith MCP endpoints implementing the streaming HTTP aspects of the MCP specification (GET + POST) as a default setting for CQL Studio's hosted and downloadable distributions.

This will be used by the in-browser agentic client alongside a separate FHIR data/content endpoint (running HAPI with MCP) to create and manage higher-level FHIR Resources, namely Library (CQL) and Measure. For example, a user should be able to give the instruction, "Research prevailing expert clinical definitions of 'non-smoker' and any related governing definitions and then implement a CQL Library providing those functions based on the FHIR data model", and have the terminology MCP endpoint be a starting place for efficient ValueSet, ConceptMap, and CodeSystem search and supporting operations.

[grahamegrieve]

ok what would such an MCP endpoint actually do?

[preston]

When connecting agents to FHIR services, it's common to use some form of MCP proxy that can be used by orchestrating clients that don't have their own native FHIR client or general FHIR awareness. A first easy win would be to just re-expose endpoints for the most frequently used terminology-related readonly calls over MCP, especially anything related to searching/filtering. This will enable agents to connect directly to an authoritative terminology server for codings and hopefully greatly reduce terminology-level hallucinations via this simple plug-and-play connection.