Handoff

A handoff is a compact record of ONE task being handed over. It records what the next actor must know to continue and complete the work — no more, no less.

It anchors at the seam: the joint where this session's work ends and the next's begins. The seam is a concept; in rosary it is addressed by an anchor bead, but the two are not identical — a session has exactly one seam even when it touches several beads or none. Reframing from "which bead?" to "where is the seam?" is what lets this skill anchor cleanly regardless of how messy the session was.

MCP dependency: rosary (rsry_*). Uses rsry_agent_session_message_record, rsry_bead_comment, rsry_workspace_checkpoint, rsry_bead_create, rsry_bead_history, rsry_dispatch_history, rsry_agent_run_events, rsry_status, rsry_expand_ref, rsry_list_beads, rsry_active. If rosary is unavailable, fall back to WRITE step 5.4 only (the /tmp markdown) and tell the user the graph anchor was skipped.

The invocation argument ($ARGUMENTS) answers "what will the next session be used for?" — it is the sole source of scope. Every field you write must trace back to it.

0. Resolve mode

If $ARGUMENTS begins with --resume, this is a pickup: go to §6 RESUME. Otherwise this is a WRITE handoff: continue with §1.

1. Resolve the seam (WRITE)

The mailbox entry needs exactly one anchor bead. Resolve it by this precedence. Detection proposes; the human confirms — never anchor a handoff silently (rung 1 is already user-named, so it needs no confirm). Anchoring to the wrong bead quietly poisons the next session.

1. Explicit — if $ARGUMENTS starts with a bead id (e.g. agents-a40691), that is the seam. Use it, no guessing.
2. Detected spine — otherwise infer the spine bead, trying in order: a. active dispatch — rsry_active / rsry_dispatch_history b. current jj bookmark / git branch — jj bookmark list or git branch --show-current, matched against open beads c. most-recently-touched bead — rsry_bead_history Present the resolved seam to the user and get a one-tap confirm before writing anything. This is the common (~80%) path.
3. Minted — only if all three detectors return nothing OR mutually disagree (i.e. detection is unconfident; a single confident detector short-circuits to rung 2): mint a seam to be the anchor rather than jamming the handoff onto an unrelated bead:

   rsry_bead_create(
     issue_type = research | design,        # exempt from the runnable close-condition gate
     title      = "handoff: <slug>",
     acceptance_criteria = <the one-sentence task from §3>)

   Then link the in-play beads to it via a discovered-from dependency (rsry_bead_link).

Record which rung fired as seam.resolution in the payload (§4). Collect every other in-play bead into seam.related so the constellation survives no matter which rung won.

2. Bootstrap from state (WRITE)

Reconstruct what happened from rosary before summarizing from the conversation — so the handoff survives a compacted context window:

• rsry_bead_history <seam> — what changed on the bead this session.
• rsry_dispatch_history — which agents touched what.
• rsry_agent_run_events — prior events on the bead.

Use the conversation only for the glue rosary cannot see: the why, the dead ends you ruled out, the judgment calls. Rosary is the skeleton; the conversation is the marrow.

3. Derive scope from the task verb (WRITE)

Restate the task in ONE sentence taken from $ARGUMENTS — not from where the session currently sits. Then classify the deliverable by the verb:

• "find out / investigate / determine / check whether" → task.deliverable = "report". Do NOT include a recommendation, a decision, a chosen fix, or an implementation/next-step plan. The deliverable is the finding.
• "implement / fix / add / migrate" → task.deliverable = "change". The deliverable is the change itself.

deliverable is a typed field in the payload, and §6 restates it at pickup — so scope creep is caught when the next session starts, not just when this one ends.

Proofread gate: before writing, re-read every field you intend to emit against the one sentence, and cut anything that does not help the receiving agent do exactly that task. Padding is as much a failure as omission.

4. Build the payload

Build ONE structured object. Both the bead comment (§5.2) and the /tmp view (§5.4) render from it — one source, two views. Omit empty fields; do not pad. Redact secrets (API keys, passwords, PII) before writing anything.

{
  "schema_version": 1,
  "seam": {
    "anchor_bead": "agents-395c30",
    "resolution": "detected-spine",      // explicit | detected-spine | minted
    "related": ["agents-56509c"]          // satellite beads in play
  },
  "task": {
    "one_sentence": "Finish the eve.dev service spike and report findings.",
    "deliverable": "report"               // report | change — derived from the verb (§3)
  },
  "state": {
    "checkpoint": "<jj-change-id>",        // from §5.3; omit if no code changed
    "branch": "eve-spike",
    "uncommitted": false
  },
  "acceptance_criteria": ["..."],          // maps to the rosary bead acceptance_criteria field
  "how_to_verify": "runnable command or steps",
  "do_not_touch": ["path or claim that must not change"],
  "out_of_scope": ["work the receiving agent must not start"],
  "references": ["path", "url", "PR#"],    // reference, do not duplicate
  "suggested_skills": ["skill-name"]       // only those strictly necessary
}

5. Materialize (WRITE)

Write these four artifacts, in this order:

1. Mailbox — machine truth.

   rsry_agent_session_message_record(
     repo       = <repo>,
     bead_id    = <seam>,
     event_type = "handoff_message",
     message    = <task.one_sentence>,
     payload    = <the §4 object>)

   This is rosary's own handoff primitive; the next session drains it via rsry_agent_run_events. Do NOT attempt provider-native session_ref delivery — record the event only; addressed delivery is out of scope.
2. Bead comment — human trail. rsry_bead_comment(id=<seam>, body=<rendered markdown>). Render the markdown from the payload using the schema in §8. This lives in the graph next to the work, where a human scanning the bead will find it.
3. Workspace checkpoint — resumable tree. ONLY if code changed this session: rsry_workspace_checkpoint(bead_id=<seam>, repo_path=<repo>, message="handoff: <slug>"). Store the returned jj change id as state.checkpoint. If no code changed, SKIP — do not mint empty commits.
4. /tmp view — human grab. Write the same rendered markdown (§8) to /tmp/handoff-<YYYY-MM-DD>-<slug>.md. <slug> is 2–4 kebab words, human-legible, with NO session/bead ids in the filename.

When done, print only the /tmp path. No summary, no extra commentary.

6. RESUME (--resume [<bead-id>])

1. Drain. rsry_agent_run_events filtered to event_type == "handoff_message" for the repo (and the bead, if an id was passed). Take the latest entry; read its payload.
2. Land on the tree. If payload.state.checkpoint is set, check out that jj change so the working tree matches the state the handoff was written against.
3. Re-validate live state. The mailbox entry is an OBSERVATION at handoff time, not current truth. Run rsry_status + rsry_expand_ref <seam> (or rsry_list_beads). If the seam bead is closed or reassigned, HARD-STOP: print a drift report (what the handoff assumed vs what is true now) and let the human decide — reopen, re-anchor, or abandon. Never silently resume onto moved state.
4. Restate & begin. Restate payload.task.one_sentence and payload.task.deliverable, and honor the deliverable class: a report handoff must not start making changes. Load any payload.suggested_skills, then begin the work.

7. Invariants

• Seam is confirmed, never silent — except the explicit rung, where the user named it.
• Mailbox is a snapshot; RESUME re-validates — never act on a stale bead.
• Reference, don't duplicate — cite paths/URLs; never re-summarize what is already verbatim in the graph or the repo.
• Redact secrets before any artifact is written.
• Human-legible /tmp name — 2–4 kebab words, no ids.
• No code changed → no checkpoint — do not mint empty jj commits.
• Scope from the task, not the conversation — the one sentence is the only source of scope; match the deliverable to its verb.

8. Rendered-markdown schema (bead comment + /tmp view)

Both the §5.2 bead comment and the §5.4 /tmp file use this shape. Empty sections are omitted — do not pad.

# Handoff

Short summary of what the parent session has been generally about.

## Task

<the one-sentence task, then the compact detail the next actor needs>

## Do Not Touch

<what cannot be changed / touched>

## Out of scope

<work the receiving agent must not start>

## Acceptance Criteria

<what needs to happen to call it done>

## How to verify

<how to verify the outcome is as desired — a runnable command if possible>

## References

<paths/URLs only: relevant docs, PR/issues, the seam bead + related beads>

## Skills

<suggested skills to load — only those strictly necessary>