{"slug":"music-theory-x402tookit-com-roman-numerals-ae9bab","title":"Roman numeral analysis of a chord progression in a key","host":"music-theory.x402tookit.com","method":"GET","resource":"https://music-theory.x402tookit.com/roman-numerals","category":"other","description":"Roman numeral analysis of a chord progression in a key: numerals, inversions, borrowed chords, secondary dominants.","price_listed":0.02,"price_asked":0.02,"state":"answering","state_label":"Answering","checks_7d":1,"answered_7d":1,"latency_ms_median":506,"reported_calls_30d":1,"reported_payers_30d":1,"networks":["eip155:137","eip155:42161","eip155:8453","solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"key":"C","progression":"C Am F G7"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"key":{"description":"Key of the progression: C, G, Am, F# minor","type":"string"},"progression":{"description":"Chords separated by spaces, commas or bars: C Am F G7","type":"string"}},"required":["key","progression"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"analysis":{"items":{"properties":{"chord":{"type":["null","string"]},"degreeFromTonic":{"type":["null","number"]},"diatonic":{"type":["boolean","null"]},"diatonicNote":{"type":["null","string"]},"numeral":{"type":["null","string"]},"role":{"type":["null","string"]},"root":{"type":["null","string"]}},"type":"object"},"type":["array","null"]},"asOf":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"disclaimer":{"type":["null","string"]},"key":{"type":["null","string"]},"notChecked":{"items":{"type":"string"},"type":["array","null"]},"numerals":{"items":{"type":"string"},"type":["array","null"]},"reasons":{"items":{"type":"string"},"type":["array","null"]},"source":{"type":["null","string"]},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]}},"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-21","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.02,"price_match":true,"latency_ms":506,"error":null}],"description_full":"Roman numeral analysis of a chord progression in a key: numerals, inversions, borrowed chords, secondary dominants.","last_updated":"2026-10-20T20:46:48.988Z","schemes":["exact"]}