spatial9-stem-split

Separate a mixed song into instrument stems (vocals, drums, bass and more) as WAV files with the Spatial9 MCP server. Use when the user asks for stems, an acapella, an instrumental, a karaoke version or separate instrument tracks.

Spatial9 stem split

Requires the Spatial9 MCP server at https://spatial9.ai/mcp (or https://spatial9.ai/mcp/free for one free split).

Steps

1. Get the source as source_url (public https link) or upload_id (from create_upload_link).
2. Call split_stems with title and an idempotency_key.
3. A split usually takes 4 to 8 minutes. Poll get_job_status every 30 to 60 seconds.
4. When finished, call get_downloads. Each stem is listed as stem:<stem_id>. When it is ready, stems_package is a single ZIP with every stem.
5. Stems marked quiet (silent or near_silent) have almost no sound. Offer combine_quiet_stems to merge them into one file.

Follow-ups to offer

• "Make an immersive mix from these stems": hand off to the spatial9-immersive-mix skill with create_from_stems.
• "Preview it on headphones first": preview_chorus.

Rules

• Only separate music the user owns or has permission to use.
• Never invent download links.

Files

• spatial9-stem-split/SKILL.md

Download every skill as a zip