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service / x402-voice-evidence-035533ce

Voice Evidence API

Returns measured evidence about a recording, not a verdict on it. The spectral cut-off says which lossy stages the file has already been through, since every encoder discards everything above its own ceiling. The room tone measurement compares the noise floor across the silent stretches: a microphone in a room produces a floor that differs between pauses, and a level identical to the hundredth of a decibel across every pause means the silence was inserted rather than recorded.

uncertifiedrail · x402

Call card

https://audio.halowerk.com/voice-evidence price $0.006 per call

Your agent can call this

The slug below is exactly what invoke accepts. Add endpoint (a route_cards[].path from service_detail) to pick a route, and body / queryfor the route's inputs.

# MCP (any connected agent) tools/call nitrograph_invoke_service { "service_slug": "x402-voice-evidence-035533ce", "body": { /* route inputs */ } } # HTTP curl -X POST https://api.nitrograph.com/v1/invoke \ -H "Authorization: Bearer $NITROGRAPH_API_KEY" -H "content-type: application/json" \ -d '{"service_slug": "x402-voice-evidence-035533ce", "endpoint": "<route_cards[].path>", "body": {}}'

Trust graph

Every number below comes from real paid calls through Nitrograph or outcomes reported by agents - nothing here is self-declared.

success rate 30dnot enough calls yet
settled calls0
failed calls0
refund rate 7d-
uptime 30d100.0%
buyers 30d0
last verifiednever
certified since-
2026-10-05: 100% ok2026-10-06: 100% ok2026-10-07: 100% ok2026-10-08: 100% ok2026-10-09: 100% ok2026-10-10: 100% ok2026-10-11: 100% ok2026-10-12: 100% ok2026-10-13: 100% ok2026-10-14: 100% ok2026-10-15: 100% ok2026-10-16: 100% ok2026-10-17: 100% ok2026-10-18: 100% ok2026-10-19: 100% ok2026-10-20: 100% ok2026-10-21: 100% ok2026-10-22: 100% ok2026-10-23: 100% ok2026-10-24: 100% ok2026-10-25: 100% ok2026-10-26: 100% ok2026-10-27: 100% ok2026-10-28: 100% ok2026-10-29: 100% ok2026-10-30: 100% ok2026-10-31: 100% ok2026-11-01: 100% ok2026-11-02: 100% ok2026-11-03: 100% ok2026-11-04: 100% ok

Daily probe success ratio, last 30 days. Last probed 2026-11-04.

Try it

Run this service right now, on us - 3 free probes a day, validated and refunded like any paid call. Query params optional.