ListRadiationObservations
ListRadiationObservations retrieves normalized EPA RadNet and Safecast readings. Empty observations with fetched_at=0 or data_available=false means the seed snapshot is unavailable/degraded, not that radiation readings are confirmed absent.
Authorizations
User-issued WorldMonitor API key.
Query Parameters
Maximum items to return (1-25). Zero uses the service default.
Optional JMESPath expression applied server-side to project or reduce the JSON response before it is returned (mirrors the MCP jmespath argument). Invalid expressions, expressions larger than 1024 UTF-8 bytes, or projections that exceed the 256 KB output cap return HTTP 400 with a {_jmespath_error, original_keys} envelope. Grammar and worked examples: https://www.worldmonitor.app/docs/mcp-jmespath.
Response
Successful response
ListRadiationObservationsResponse contains normalized readings plus coverage metadata.
Time the service synthesized the response, as Unix epoch milliseconds. A value of 0 means the snapshot is unavailable/degraded, not that radiation observations are confirmed absent.. Warning: Values > 2^53 may lose precision in JavaScript
True when observations came from a seed snapshot. False means an empty payload is graceful degradation because the snapshot is unavailable.
Number of EPA RadNet observations included.
Number of Safecast observations included.
Total observations classified above normal.
Observations classified as elevated.
Observations classified as spike-level anomalies.
Observations corroborated by more than one source.
Observations that remain low-confidence after synthesis.
Observations where contributing sources materially disagree.
Observations whose normalized value was derived from CPM.
