Inventory APIs get consumed by developers reading docs and by agents discovering tools. Separate web docs, prompt pastes, and hand-written schemas guarantee drift; one OpenAPI file produces both.
A concrete Cloud walkthrough: publish a managed Streamable HTTP MCP endpoint from one spec, expose twelve operations out of forty-seven, gate agents with a rotated bearer key, inject upstream auth, and pin the partner to an immutable version.
Hand-writing tool wrappers around existing order and inventory endpoints means maintaining every contract twice. Generate the MCP server from the OpenAPI spec, start with read-only tools, and widen the surface deliberately.
AI agents need tools, and hand-writing MCP wrappers around your API recreates the exact drift problem OpenAPI solved. Powerduck Cloud turns one spec into hosted docs and a ready-to-use MCP endpoint.
Generated screens fail on limit versus pageSize, data.records versus data.items, cents versus dollars. The fix is not a better prompt; it is letting the agent query the real contract and verify against real responses.
Every new coding assistant starts with the same ritual: paste the docs, explain the fields, warn about stale versions. A local spec served over MCP makes that context permanent.
