Tutorial: Receipts-First Agents with LangGraph + Supabase Edge

Architecture

• LangGraph orchestrator with receipts baked into every edge.
• Supabase Edge Functions to sign tool calls and stream events.
• Postgres + Vault for encrypted traces and reversible toggles.

Build steps

1. Scaffold graph nodes with explicit approvals and rollback handlers.
2. Add an event bus that logs tool inputs/outputs plus latency + cost metrics.
3. Render a receipts timeline in React with filters for model version and decision ID.
4. Write CI evals that replay risky prompts against a staging graph before every deploy.

What you get

A production-ready starter with receipts UI, audit-friendly logs, and a “pause agent” switch PMs can use without paging engineering.