Handoff body

Use DOC, data.kind=handoff. Link task, specification, selected artifact, session/run evidence and prior handoff.

## Destination and accepted changes
## Settled decisions and relevant lessons
## Current repository/worktree/base/head
## Implemented
## Independently verified
## Reported but unverified
## Pending scope and blockers
## Ambiguous commands / operation keys
## Exact next action and prerequisites
## Context to load / related references

Example next action: “Read the selected variant and the updated task; run the reconnect reproduction in the existing fixture worktree. The last command was acknowledged at revision 3; do not repeat its create operation. Live-provider acceptance still needs owner model selection.”

Do not put credentials or session login tokens into the handoff. Provider session identity may be a provenance link, but a resume claim must come from supported continuation rather than an invented fresh session presented as the same one.