{"uid":"cap_fZv9KUTIYUHh1_riZskRw","slug":"relaystation-audio-mix-55d01fab","name":"Relaystation Audio Mix","description":"$0.0005/MB. Mix multiple audio tracks down to one (amix), optional loudness normalize — voiceover + music in one call. 1¢ x402 min; remainder auto-credits — relaystation.ai/penny","url":"https://api.relaystation.ai/v1/media/audio-mix","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","properties":{"file":{"type":"object","description":"cputools input-source: { inline: <base64 ≤ 4 MiB> } or { inputKey: <scratch key ≤ 50 MB> }. The input container must sniff (ffprobe) to the live allowlist (operator-tunable cputools.media.input_formats): 3g2, 3gp, aac, asf, avi, flac, flv, gif, m4a, m4v, matroska, mj2, mov, mov,mp4,m4a,3gp,3g2,mj2, mp3, mp4, mpeg, mpegts, mpegvideo, ogg, wav, webm, wmv. An off-list input is a free 422 UNSUPPORTED_FORMAT."},"format":{"enum":["mp3","m4a","aac","wav","ogg","flac"],"type":"string"},"inputs":{"type":"array","items":{"type":"object","description":"cputools input-source: { inline: <base64 ≤ 4 MiB> } or { inputKey: <scratch key from /v1/cputools/upload-url, ≤ 50 MB> }."},"maxItems":8,"minItems":1},"normalize":{"type":"boolean"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST","PUT","PATCH"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_oNmiJf8LGqGYZ1kt-615e","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Mixes multiple audio tracks into a single output using amix, with optional loudness normalization — ideal for combining voiceover and background music in one API call","exampleAgentPrompt":"Mix my voiceover recording and background music track into a single audio file, and apply loudness normalization so they balance well together.","exampleUseCases":[{"title":"Podcast voiceover and music blend","prompt":"I have a narration track and a soft background music track for my podcast intro — can you mix them together into one audio file with loudness normalization turned on so the music doesn't overpower the voice?"},{"title":"Video ad audio post-production","prompt":"Combine these three audio layers — the spokesperson voiceover, the sound effects track, and the background music — into a single mixed-down audio file I can attach to my video ad."},{"title":"Automated audiobook chapter assembly","prompt":"I've got a chapter narration file and a subtle ambient music track — merge them into one normalized audio file for the audiobook chapter."}],"resultDescription":"A single mixed-down audio file combining all input tracks, optionally loudness-normalized. Pricing is $0.0005/MB of input data with a 1¢ minimum; any remainder is auto-credited to the account.","failureModes":["Unsupported audio format returns an error","Missing or malformed audio track input causes a 400 bad request","Exceeding size or track count limits may result in rejection","Insufficient USDC balance to cover the call results in payment failure","Network timeout on large audio files"],"whenToPreferThis":"Choose this endpoint when you need to combine multiple audio tracks (e.g. voiceover plus music) into a single output file programmatically, especially within an automated agent workflow where per-MB pricing and optional loudness normalization are desirable. Ideal for content pipelines, podcast production, video post-production, and any use case requiring serverless audio mixing without managing FFmpeg infrastructure.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T17:51:33.220Z","isFirstParty":false}