Seat Continuity and Handover

A pair of primitive families that separate who is sitting in a seat from what the seat itself is:

1. Occupant-creation primitives — resume, fork, rebuild, fresh — produce a candidate new occupant. Answer: "where did the new occupant come from?"
2. Seat-binding primitives — seat handover, later seat transfer / seat retire / seat swap — bind a candidate occupant into the topology. Answer: "what happened to the stable seat identity?"

Core architectural decision: stable seat identity, fluid occupant identity, explicit provenance. Today's lead2/lead3/lead4/lead5 pattern encodes successor lineage into seat names — that's the wrong shape. Stable seat name + separately-recorded provenance trail is the right shape.

Use this when

• Replacing a seat's occupant via rebuild, fork, fresh, or future seat-handover
• Choosing old-occupant disposition: retire / advise / shadow
• Reasoning about whether a seat's lineage is stable or has drifted
• Reading or writing the provenance record for a seat
• Designing or auditing topology stability across an occupant change

Don't use this when

• The seat is freshly created (no occupant to replace) — use rig launch / rig expand directly
• The intent is to change topology shape (add/remove seats), not replace an occupant — use topology-mutation primitives

The two-outcome honesty model

Every seat-binding operation produces two independent outcomes:

continuityOutcome: rebuilt | resumed | forked | fresh | failed
seatBindingOutcome: handed_over | partial | failed | unchanged

These can disagree honestly. Examples:

• continuityOutcome: failed + seatBindingOutcome: unchanged — new occupant didn't materialize; seat correctly retains old occupant.
• continuityOutcome: rebuilt + seatBindingOutcome: failed — candidate created OK; bind failed mid-flight; provenance records the gap.

Don't collapse these into one outcome. The system can describe what actually happened only if the two are recorded independently.

Provenance record (durable, queryable)

Every handover writes:

• seat id
• old occupant id
• new occupant id
• creation mode (resume/fork/rebuild/fresh)
• source artifacts used
• whether old occupant remains alive as advisor/shadow
• operator or loop that initiated the motion
• timestamp
• result (handed_over / partial / failed)

This is the system's truth-source for "how did the current occupant get there." Without it, the control plane shows the current occupant but not the legitimacy of the transition.

State models — independent

Occupant-creation state (per candidate)

1. Requested — input to rebuild/fork/fresh/resume
2. Realized — runtime/artifact path produced an occupant with managed-seat shape
3. Failed — candidate didn't materialize; continuityOutcome: failed

Seat-binding state (per seat)

1. Stable — current occupant attached, no in-flight binding
2. Binding — handover in progress
3. Bound — handover succeeded; provenance record written
4. Unchanged — bind failed before completion; seat retains old occupant

A seat stays Stable even if multiple candidate-occupants were produced and discarded.

Failure modes (5)

1. Candidate creation failed — rebuild couldn't synthesize from artifacts; fork couldn't resolve session_source; fresh couldn't launch. Action: bind operation does not begin; seat unchanged; provenance records the failed candidate-creation step.
2. Old occupant cannot be detached cleanly — runtime hung, tmux locked, etc. Action: bind halts mid-flight; seat enters Binding state with explicit "halted" sub-status; operator alerted. Do NOT auto-rollback by reattaching old-occupant if detach didn't complete cleanly.
3. Bind succeeded but provenance write failed — disk/db error. Action: not durable until provenance writes; treat as Binding halted, not Bound.
4. Old occupant disposition unfulfillable — operator requested advise (keep alive as advisor) but runtime can't keep old alive. Action: degrade to retire with explicit notification, OR fail if operator passed strict-disposition flag.
5. Concurrent handover attempts — two operations target the same seat. Action: serialize by seat-id lock; second attempt refuses with clear error.

Hard boundaries (do-not list; verbatim)

• Do NOT collapse `rebuild` and `seat handover` into one primitive. The design specifically separates them so the system can describe what actually happened.
• Do NOT introduce successor-suffix seat names (lead2/lead3). Stable seat identity is the architectural goal.
• Do NOT report `seatBindingOutcome: handed_over` if the provenance record didn't write durably.
• Do NOT auto-rollback a half-completed handover by re-attaching the old occupant unless detach completed cleanly first.

Composition: seat handover over fork

Once session_source fork v1 lands (already shipped at openrig c7b6df1), the next composition is seat handover over fork: candidate occupant created via fork, bound into the existing seat via handover. Continuity outcome is forked; binding outcome is independent.

Currently shipped vs deferred

• Option A (rebuild) shipped at openrig 578bd5c (2026-04-30): session_source.mode: rebuild with ref.kind: artifact_set; identity-honesty bedrock at 4 layers (schema dispatch, orchestrator threading, SQLite read-back, negative-grep on resolver output). 26/26 Tier 1 cases green; full daemon regression 2146/2146 PASS.
• Option B partially shipped, partially deferred to Mode 3: the rig seat handover CLI exists as a planning/observability surface — status <seat> reads the seat-handover observability tables (migration 021); handover <seat> plans a safe two-phase handover sequence with actual execution flowing through existing seat-launch surfaces under operator gating. Full code-direct SeatHandoverService daemon module + seat-binding-outcome provenance record + nodes-table provenance migration remain deferred to Mode 3. MVP composition seat handover over fork is highest-leverage v1.

Why load-bearing for RSI

Any recursive seat-refresh loop must be able to replace an occupant while keeping topology stable. Without these primitives, RSI loops will either accumulate suffixed seat names (lineage leaking into identity) or destabilize topology references on each cycle. Provenance must be durable AND queryable so RSI loops can decide whether a seat is fresh enough to receive new work or needs re-handover.

See also

• claude-compaction-restore skill — packet-driven restore after Claude compaction
• agent-startup-and-context-ingestion skill — ingestion path for restore packets at agent boot