Client API Handoff Dossier (Handoff)

Client API Handoff Dossier (Handoff)

1. 01

   Freeze the endpoint contract before the final delivery call

   Export the OpenAPI spec at the exact commit the client will run, tag it, and treat any post-freeze change as a new scope item with its own estimate.

2. 02

   Map every credential the client must own, not borrow

   List gateway keys, LLM provider tokens, webhook signing secrets, and database roles separately, and mark which ones currently sit in an agency-owned account that has to be transferred.

3. 03

   Write the failure runbook in the client's language, not the engineer's

   For each critical endpoint, state what breaks, who gets paged, and the first three diagnostic commands, so a client-side generalist can act at 2am without calling your on-call.

4. 04

   Publish the traffic and spend baseline alongside the docs

   Record 30-day request volume, p95 latency, and monthly LLM or gateway spend so the client can tell normal from abnormal in week one, and so your retainer renewal has a number attached.

5. 05

   Run one live incident drill with the client team present

   Disable a non-production key or force a rate-limit breach and watch them respond; the gaps that surface here are the honest scope of the support retainer you are proposing.

6. 06

   Hand over the documentation surface, not just a PDF

   Move the reference into a hosted portal the client can edit, and confirm who owns the changelog going forward, because stale docs become your support ticket queue.

7. 07

   Close with a 30-day stability window and named exit criteria

   Define the error-rate and uptime thresholds that end hypercare, and put the date in the contract so the handoff has a finish line instead of drifting into unpaid maintenance.