version: "1.0.0" name: separate-stems description: Split a song into vocals, drums, bass and more, or isolate one instrument from a 45-instrument catalog. license: MIT

Skill: separate-stems

Split any song into isolated stems — vocals, drums, bass, guitar, piano — or isolate a single instrument from a 45-instrument catalog, for remixing, karaoke, or sampling. AudioStems is AudioPod's stem separation engine.

When to use

Invoke when the user wants to:

• Remove vocals from a song (karaoke / instrumental track)
• Isolate a specific instrument (acapella, drum loop, bass-only)
• Remix or sample a track legally without a multitrack stem pack
• Build a karaoke file with an instrumental + lyric overlay

API

POST https://api.audiopod.ai/api/v1/stem-extraction/api/extract

Headers:

• X-API-Key: ap_your_api_key (or Authorization: Bearer ap_your_api_key)
• Content-Type: multipart/form-data

Body (form-data):

• file: audio file (MP3, WAV, FLAC, OGG) — or url to a public audio file
• mode: single · two (vocals + instrumental) · four (default) · six ·

producer · studio · mastering

• stem: only for mode=single — one of vocals, drums, bass, guitar,

piano, other

The producer, studio, and mastering modes decompose the drum kit and split the bass, yielding up to 8, 12, and 16 stems respectively — the exact count depends on what the track actually contains (a song with no cymbals yields no cymbal stem). Plan those as "up to N", never a fixed number.

Plan gating: producer needs Creator or above; studio and mastering need Pro or above. single, two, four, and six work on every plan including the free tier.

Isolating one instrument from the full catalog

mode=single on the endpoint above accepts the six core stems. To reach the full 45-instrument catalog (saxophone, violin, lead vocal, electric guitar, …), use:

POST https://api.audiopod.ai/api/v1/stem-extraction/extract/advanced

• single_stem: a catalog id — returns that instrument plus an everything-else

track

• exclude_stems: a JSON array with one id — returns the track without it

List the catalog with GET /api/v1/stem-extraction/catalog. Each entry carries an id, a label, the public_tier it requires, and an allowed boolean for the calling key — check allowed before dispatching rather than handling a rejection. Catalog isolation beyond the seven core stems requires Creator or above.

Response

{ "job_id": 12345, "status": "PENDING" }

job_id is an integer, unique within the stem-extraction tool.

Poll GET /api/v1/stem-extraction/status/{job_id} for the per-stem download URLs. (Job IDs are per-tool — there is no generic /api/v1/jobs/{job_id} endpoint.)

Notes

• Input length caps by plan: Free/Basic 30 minutes, Creator 2 hours, Pro 5

hours, Studio 10 hours

• Upload size caps by plan: Free/Basic 250 MB, Creator 500 MB, Pro and Studio 1 GB
• Stems are royalty-free for personal and commercial use on paid plans