Hand the session over

The owner typed /vault-handoff, so updating the cross-session record is authorised for this run. A coding agent carries no memory between sessions: HANDOFF.md is that memory, and a future session trusts it over its own assumptions. Do each step; skip one that has nothing to do.

1. Session log. Append an entry to HANDOFF.md's ## Session Log: what happened, what was decided and why, and what was deliberately left alone and why. Record reasoning, not just actions, so a future session does not "fix" a deliberate choice.
2. HANDOFF.md. Refresh Current State, Waiting On and Open Threads; add a lasting decision under Decisions; bump the date and the session count. HANDOFF.md is read every session, so its size is a permanent tax: the build warns when it passes its budget in CONTEXT_BUDGET_TOKENS (tools/lib/rules.js). The remedy is to move detail out, never to delete or summarise it to fit (D01): the oldest session entries go word for word into wiki/tooling/worklog/vault-session-log.md (a kind: log node, one ### YYYY-MM-DD (D-Mon-YY) heading per session day; create it the first time, following .claude/rules/wiki-writing.md), and a decision's full reasoning into a detail node in wiki/tooling/, leaving one line here.
3. AGENTS.md and the rules. If a rule changed this session, revise the file that holds it — the always-on core, AGENTS.md, or a .claude/rules/ file — and grep the vault and tools/ for its old wording (D20). If nothing changed, say so and leave them.
4. Global memory at {{MEMORY_PATH}}: anything important enough to outlive this vault, one fact per file, with its pointer in MEMORY.md.
5. Build, self-test, commit, push. node tools/build-index.js must end PROBLEMS: none; run node tools/selftest.js if tooling changed. Check the exit status, never a piped tail. Commit with the counts that changed — nodes, sections, edges — and push.
6. Report in a few lines what was updated, and anything still waiting in raw/ for /vault-compile.

Why this is gated

The session record is the owner's to start, like the compile and the audits (inherited from Vifert's vault, 24 September 2026, D87). The agent still commits and pushes its own work once the build is clean, and at the end of a session that changed the vault reminds the owner once, in one line, to type /vault-handoff.