feat: Agent-native ecosystem — open API documentation and third-party MCP integration

[ChuxiJ]

Context

From DAW tech stack research: No other DAW — desktop or web — offers programmatic Agent/AI control. Our window.__store API and integrated terminal are completely unique in the industry. This is our strongest differentiator and should be treated as a platform feature.

Bitwig's Java extension API is the closest analog in desktop DAWs, but it requires Java knowledge and can't be driven by AI agents.

Goal

Formalize and document the Agent-native API so third-party agents, MCP servers, and automation tools can control ACE-Step DAW programmatically.

Acceptance Criteria

• Public API documentation for all window.__store actions (auto-generated from TypeScript types)
• MCP server specification: expose DAW actions as MCP tools
• Example: "Claude agent that composes a full song from a text prompt using DAW API"
• Example: "Automation script that applies mastering chain to all tracks"
• Rate limiting and permission model for external agent access
• API versioning strategy (breaking change policy)
• Developer guide: "Build your first DAW agent"

Strategic Context

Competitive moat: Zero competitors have this capability
Industry trend: AI agents as first-class application users (2025-2026 wave)
Builds on: window.__store, actionApi.ts, commandPalette.ts

Part of: DAW Best Practices Research Series

[ChuxiJ]

Priority Update: P1 → P3

Strategic ecosystem feature. Deferred until core experience polish (P0/P1) is complete. Re-prioritized as part of Experience Polish Series.

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Generated by Claude Code