API-First Architecture

Definition

Hard architectural constraint: every capability accessible via UI must also be available via API. Enables agents to live outside the Harmony product (Claude Code, OpenAI workflows, CRM plugins, etc.) and opens distribution through AI platform ecosystems.

Related decisions

• DEC-018 — Product must be API-first (the constraint itself)
• DEC-017 — Bring-your-own-agent support depends on this

Sources

• vision-2026-04-15 — the architectural commitment

Related entities

• saar-arbel, vitali — joint owners (AI-018)
• anthropic — possible distribution partner via Claude Code plugin

Related concepts

• brain-layer — what is being exposed via API
• bring-your-own-agent — depends on API-first
• wedge-strategy — distribution lever

Differentiator notes

Competitors like elevenlabs are API-first for voice, but none combine opinionated sales agents + API-first + cross-funnel intelligence. That triad is the moat.