Overview - Locus

Five endpoints, one engine. retrieve and retrieve/stream are the SAME answer from the SAME service: only the way it is delivered differs. drugs and feedback are what comes around it — before a drug card is displayed, after an answer is read.

Endpoint	Verb	Use it for
`/v2/retrieve`	POST	A cited answer in one call. The simplest path.
`/v2/retrieve/stream`	POST	The same answer, streamed step by step (NDJSON).
`/v2/drugs/rubrics/{id}`	GET	The full text of a truncated SmPC section.
`/v2/drugs/specialites/{cis}`	GET	Another specialty’s SmPC, loaded on expand.
`/v2/sources`	GET	The publishers a retrieval can be restricted to.
`/v2/feedback`	POST	Attach a thumb to an answer already served.

Which one to call

A script, a batch, a back end

/v2/retrieve. One call, one payload. Nothing to assemble.

A UI where someone is waiting

/v2/retrieve/stream. Steps arrive as they happen, so the wait can be watched.

What you will not find here

The knowledge write plane — PDF ingest, summarization, knowledge-unit extraction — has no route. It runs as a batch, through the locus CLI, where the source PDFs are. An API exposing it would promise work the server cannot do: the PDFs are not on its disk.