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service / x402-chord-053afa80

Build a chord

Build a chord from a root note and quality (major, minor, dim, aug, maj7, min7, dom7, dim7, half-dim7, sus2, sus4, maj6, min6). Notes are spelled by stacked thirds (C dom7 → C E G Bb). Returns the note names, MIDI numbers and semitone intervals.

uncertifiedrail · x402

Call card

https://music.openverbs.com/v1/chord price $0.002 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-chord-053afa80", "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-chord-053afa80", "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 30d73.0%
buyers 30d0
last verifiednever
certified since-
2026-09-27: 100% ok2026-09-28: 100% ok2026-09-29: 100% ok2026-09-30: 0% ok2026-10-01: 100% ok2026-10-02: 100% ok2026-10-03: 50% ok2026-10-05: 0% ok2026-10-06: 0% ok2026-10-08: 100% ok2026-10-09: 100% ok2026-10-10: 100% ok

Daily probe success ratio, last 30 days. Last probed 2026-10-10.

Try it

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