### Session pickup

**You own the resume point. Read the prior trail, don't redo it.**

1. Locate the prior trail. In a shell, `$PI_SESSION_FILE` names the active session's JSONL file, and it is unset for an in-memory session. Earlier sessions for this working directory are in Pi's session directory, by default under `~/.pi/agent/sessions/` and grouped by working directory, unless `PI_CODING_AGENT_SESSION_DIR` or `--session-dir` moves it. Read only the sessions for this working directory. Before grepping, reading or delegating an earlier session file, read only its first line, the session header, and check that its `cwd` is exactly this working directory: a session directory's encoded name can collide with another project's, and a directory can be shared. Skip any session whose header names another directory, or has none, without reading further. A child brief lists only the files that passed and tells the child to repeat this check before it greps or reads one. Searching other projects' sessions crosses into unrelated private work. The **recall** skill searches them for you under the same rule. A pushed branch, a handoff report or a resume note from `playbooks/pause-safely.md` is also valid evidence. Read the metadata overview and last messages first, then scan back for the decision points.
   Parse a long transcript in a subagent and keep the reduced timeline in the main thread (**principle-guard-the-context-window**).
2. Reconstruct operational state. The branch and worktree, what already landed (`git log`, `git diff` against the base), the open checklist items, the decisions made. The prior trail is authoritative input. Resist the bias to re-derive it.
3. Diff done vs pending. Compare what shipped against what was planned, name the resume point, do not re-run the prior repro or redo completed work. A "let me verify from scratch" pass means you're treating the trail as untrustworthy when it's authoritative.
4. Route the remaining work to the matching playbook and pick the verdict: continue the execution, ship a finished recommendation, ratify or override a prior conclusion, or postmortem a failed run. The pickup playbook ends here. The routed playbook owns the rest.
5. Verify the inherited claims against the original goal on the real artifact (**principle-prove-it-works**). A passing prior self-report is not the proof.

The prior agent's authority does not carry over. Re-read the current request and repository instructions before any action in `references/authorization.md`, even if the prior trail shows it was approved earlier.

**Reply:** where the prior agent stopped, what you inherited vs redid (ideally nothing redone), the resume point, and the outcome.