AuthorizationstringheaderRequired Bearer API key for programmatic World access.
Example: Bearer nos_sk_...
Aggregate semantic event matches into a compact, dense time series on the server.
Use Event Trend for a semantic signal over time without downloading the matching events. Buckets are stable under wider date ranges because retrieval uses fixed calendar-quarter partitions. Treat truncated buckets as lower bounds.
These are the fields you can build against. Nested names use dot notation; optional sections are called out in their descriptions.
idstringShort-lived handle for bucket drill-down.
Example: tr_4a45c76c941f482e
approximatebooleanAlways true because semantic candidate retrieval is bounded.
Example: true
bucketsobject[]Dense chronological time-series buckets.
Example: [{ start, event_count, coverage_sum, similarity_sum, truncated, groups }]
buckets[].startdateInclusive bucket start date.
Example: 2026-06-01
buckets[].event_countintegerRetained semantic matches in the bucket.
Example: 184
buckets[].coverage_sumintegerSum of distinct-source coverage across retained events.
Example: 612
buckets[].similarity_sumnumberSum of exact semantic similarities across retained events.
Example: 123.84
buckets[].truncatedbooleanTrue when the quarter candidate budget filled and more matches may exist.
Example: false
buckets[].groupsobjectOptional group-value metrics.
Example: { "negative": { "event_count": 91, "coverage_sum": 318, "similarity_sum": 62.17 } }
invalid_request — The date, filter, cursor, identifier, or request combination is invalid.api_key_required — No API key was sent. Send it as Authorization: Bearer <key> or the api-key header.invalid_api_key — The API key is invalid or has been revoked.access_denied — The requested archive date is outside the caller's World tier.validation_error — A body field has the wrong type or form, such as a limit sent as a string; the message names it.not_found — The requested date, entity, ticker, or event does not exist in the accessible index.cursor_expired — The cursor was minted against a replaced index build. Restart pagination from the first page.rate_limited — The request exceeded the endpoint or account rate limit. Respect Retry-After when supplied.backend_not_configured — The World backend is not configured for this deployment.api_key_auth_unavailable — API key authentication is temporarily unavailable; retry shortly.api_key_metering_unavailable — API key usage metering is temporarily unavailable, so the request was not served; wait for the Retry-After header (30 seconds) and retry.backend_error — The World backend could not be reached or did not return a valid response; retry shortly.backend_timeout — The World backend did not answer within 300 seconds; narrow the request (for example with a date window) or retry.