# TruthBear Earthquake Region Gauge (3-Leg Chain) > TruthBear Earthquake Region Gauge (3-Leg Chain) is a paid API for AI agents from api.truthbear.co, paid per call via x402, $0.25/call, status unknown (last checked 2026-09-14). Returns a 3-leg sequential seismic activity chain for a specified earthquake zone, covering leading swarm rates, current USGS micro-event rates and max magnitude, and realized felt/impact reports — descriptive only, never a forecast. ## Facts - Endpoint: GET https://api.truthbear.co/gauge/earthquake-region - Price: $0.25/call - Payment: x402 - Status: unknown - Last checked: 2026-09-14 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/truthbear-earthquake-region-gauge-3-leg-chain-e041e8d8 - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nikBIG86jnYr6PBKgfVFZ Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability truthbear-earthquake-region-gauge-3-leg-chain-e041e8d8 ``` Example prompt: Pull the 3-leg seismic activity chain for the california-san-andreas zone and tell me how many legs are currently lit, what the max magnitude is, and whether any felt reports have come in. ## When to prefer this Choose this endpoint when you need a structured, multi-stage descriptive snapshot of seismic activity for a specific named fault zone or seismic region, sourced from USGS, with built-in confidence signaling via leg count. Prefer this over raw USGS feeds when you want pre-packaged leading-to-lagging signal chaining (swarm → event rate → felt reports) without building the aggregation yourself. Do not use this for earthquake forecasting, prediction, or advisory — it is explicitly descriptive only. ## Known failure modes - 422 no_charge: no data available for the requested entity — call is not billed - Invalid or unsupported entity ID returns an error — use /gauge/catalog?signal_id= to get valid entity IDs - Network or upstream USGS data unavailability may result in partial leg data or empty response - Unrecognized query parameter (additionalProperties: false) causes request rejection ## How this service works [3-LEG] Seismic activity chain, one seismic zone (?entity=california-san-andreas): leading swarm rate, USGS micro-event rate rising - DESCRIPTIVE and explicitly not a prediction -> current current max magnitude and count -> realized felt and impact reports (confirmation gate). A chain, not one reading: confidence = how many legs are lit, in order. Sources: USGS. Descriptive only, never a forecast or advice. No data -> 422 no_charge, not billed. $0.25 per call. ## Output A JSON object representing up to three sequential chain legs in order: (1) leading swarm rate signal, (2) current USGS micro-event rate, current max magnitude, and event count, and (3) realized felt and impact report confirmations. Confidence is expressed as the number of legs currently active and in sequence. Returns a 422 no_charge if no data is available for the requested entity, and the call is not billed. ## Request schema (JSON Schema) ```json { "$schema": "https://json-schema.org/draft/2020-12/schema", "properties": { "input": { "type": "object", "properties": { "type": { "const": "http" }, "method": { "type": "string", "enum": [ "GET" ] }, "queryParams": { "type": "object", "additionalProperties": false, "properties": { "entity": { "type": "string", "description": "required - monitored object id, paired with signal_id; free list at GET /gauge/catalog?signal_id= -> signals[0].entities[]", "examples": [ "california-san-andreas", "cascadia-pnw", "alaska-aleutians", "japan", "sumatra-indonesia", "philippines" ], "x-accepted-values": { "shown": 6, "total": 18, "all": "https://api.truthbear.co/schemas/gauge-earthquake-region.input.json" } } }, "required": [ "entity" ] } }, "required": [ "type", "method", "queryParams" ] }, "output": { "type": "object", "properties": { "type": { "const": "json" }, "example": {} }, "required": [ "type" ] } } } ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "legs": { "swarm_rate": { "band": "baseline", "source_ref": "https://earthquake.usgs.gov/", "record_hash": "sha256:af7d5ce3ff47de06f8c4d68751418cb34e01c10faee588a7eaac118bd4dac5bb" }, "impact_realized": { "band": "felt", "source_ref": "https://earthquake.usgs.gov/", "record_hash": "sha256:d953b6d5974998bcc4efe988dff6b6a7cf8382c9c8e417a88974c47796215bbe" }, "current_activity": { "band": "minor", "source_ref": "https://earthquake.usgs.gov/", "record_hash": "sha256:a840cddfd12ff422ef70ddd9aa3ef96a8fbeb0bf942e7ebc4a220a24fa4b0eec" } }, "name": "California (San Andreas)", "grade": "screening-level, not decision-grade", "scope": { "full": "https://api.truthbear.co/scope/v1", "verifiability": "unknown", "monitoring_not_forecast": true, "intelligence_not_command": true }, "entity": "california-san-andreas", "nature": "This API supplies data organisation and trend description only. It is not a recommendation to act; the decision is yours. Purely descriptive - no judgement, no prediction. Official source plus record_hash; verify with the free /gauge/verify.", "provenance": { "freshness": "fresh", "age_hours_now": 0, "freshness_basis": "cadence=default; fresh<=24h; recent<=192h; dead_source>1440h; age_basis=request-time(now minus observed_at)" } } } ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/truthbear-earthquake-region-gauge-3-leg-chain-e041e8d8/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from api.truthbear.co](https://www.zero.xyz/host/api.truthbear.co/llms.txt)