Apple Docs Bridge
Connecting agents to Apple documentation while preserving the source, freshness and unknowns of each response.
Service diagram · original illustration, without third-party document content
Problem & context
An agent consulting documentation needs to know its source, when it was checked and whether it is still usable after a failure. API availability alone also does not establish that a feature is eligible in a particular context.
My contribution
Built a local MCP service for finding and retrieving API references, HIG and Support pages, using Markdown sources with a DocC JSON fallback. Added a cross-process SQLite cache, paginated responses with provenance and freshness, and regional checks limited to explicitly reviewed rules. Prepared stdio and loopback HTTP transports and a portable plugin package.
Decisions & tradeoffs
Share the cache and coordinate revalidation across processes.
Use leases, conditional requests and a shared cooldown after upstream rate limiting. Return explicitly stale evidence or an unavailable result rather than hide a failed refresh.
Make unknowns part of the result.
Separate publication date, last verification, OS/API availability and regional eligibility. An uncovered rule stays unknown; the cache is not a historical SDK archive.
Outcome
A local documentation service that returns content and provenance with an explicit freshness state. Its package and transports remain distinct from a verified installation in a particular host or a production remote service.