Create and maintain API version changes. Use when adding breaking changes to API responses/requests, creating version change files, transforming data between versions, or handling backward compatibility.

d3k assistant for debugging web apps

Debug, edit, and fix billing operations. Covers the V2 action-based architecture (attach, multiAttach, updateSubscription, allocatedInvoice, createWithDefaults, setupPayment). Use when working on billing, subscription, invoicing, or Stripe integration code.

Understand, debug, and edit Autumn checkout flows. Covers how attach creates an Autumn checkout, how public checkout routes recompute previews, how confirmation executes billing, and when Autumn checkout vs Stripe checkout vs no checkout is chosen.

Refine rough engineering thoughts into structured Linear tickets with GitHub permalinks

Reference for Autumn balance mutation logs, lock receipts, ordered deduction provenance, and finalizeLock reconciliation semantics. Use when working on lock receipts, deduction provenance, mutation-log sync, or finalize/release flows.

Fetch and inspect recent local server logs in repos that use openlogs or the `ol` CLI. Use when a user asks what happened in the server, wants recent dev-server output, needs startup errors or stack traces, or asks you to check backend logs from `openlogs tail`, command-specific logs, or `.openlogs/latest.txt`.

You are creating an **Agent Skill** - a structured capability that coding agents can discover and use to perform tasks more accurately and efficiently.