For AI agents: a documentation index is available at the root level at /llms.txt. Append /llms.txt to any URL for a page-level index, or .md for the markdown version of any page.
One request for up to 10 collections: POST /v3/collections/batch-query takes a list of collections, and each entry accepts every v3 Query parameter plus collection. A top-level query fills any entry that omits its own. Captain runs the entries at the same time, so the request takes about as long as its slowest entry. See Query Several Collections.
One ranked list per collection: results[i] answers collections[i], with the full Query response for that collection. Lists are never merged, and scores from different collections are not comparable. See Batch Query.
Failures stay in their own entry: a problem found before any search, such as an unknown collection or a missing query, fails the whole request. Once searching starts, a failed entry reports its own error in its slot and the rest still return. Retry only the failed entries.
