I3912 — A seat whose holder stopped beating is reported vacant and offered to live sessions by capability

✕BLOCKED wave 2 · p1 · implementation profile · runs alone

Part of landing-survives-any-session — Landing green work survives any session, any restart and any machine.

Objective

A claim on a seat scope (the landing seat, the release seat) whose stream stopped beating is reported as a vacant seat by mesh.state and by majordomus monitor within one expiry, with the evidence I3182 classifies it on: a missing heartbeat is reported as such and is not declared a dead worker. The vacancy is offered by capability to live sessions through I3198's fenced offer; a session that accepts holds the seat under a new fencing epoch (I3174) and consumes the newest handover published for that seat. A runtime never takes a seat by itself: only a session that can do the seat's work accepts it.

Why

On 2026-10-22 the restart of machine 641bdb94 expired the a3 and 9c seat claims; nothing reported the vacancy (the monitor folds claim_acquired and claim_released only) and nothing offered the seats until a person started a new session hours later. A review of this plan noted that a runtime claiming a seat would hold it as a phantom, since the mesh executes no work (I3198 non_scope).

Current state

mesh/state.rs marks claims of a silent stream Expired by liveness, never as an event (state.rs:735-745); ui/mesh.rs draws a seat as vacant; no code reports or offers a seat.

Desired state

Stopping the runtime that holds the landing seat makes mesh.state and the monitor report it vacant within one expiry and offers it to live sessions that declare the capability; the one that accepts holds it under a new epoch and has consumed the seat's handover.

Scope

• apps/majordomus-cli/src/mesh/cooperation.rs
• apps/majordomus-cli/src/mesh/state.rs
• apps/majordomus-cli/src/monitor
• apps/majordomus-cli/tests/mesh_cooperation.rs
• docs/MESH.md
• docs/MONITOR.md
• .ai/repo/project/issues/I3912.yaml

Dependencies

• I3174○READY An exclusive claim carries a fencing epoch, and a holder returning under an old epoch is refused
• I3182✕BLOCKED One read says which work is progressing, waiting, stalled, failed or orphaned, and on what evidence
• I3198✕BLOCKED A peer is offered an assignment by capability under a fenced lease, and accepts or refuses it with a reason

Acceptance criteria

• A seat claim whose stream stopped beating is reported vacant in mesh.state and the monitor within one expiry, naming the evidence (case a_vacant_seat_is_reported_and_offered)
• The vacancy is offered only to sessions that declare the seat's capability, and exactly one acceptance holds it under a new epoch
• A holder returning under the old epoch is refused

Validation

• bin/majordomus plan validate
• env -u MAJORDOMUS_SHARE cargo test --manifest-path apps/majordomus-cli/Cargo.toml --lib -- mesh::
• env -u MAJORDOMUS_SHARE cargo test --manifest-path apps/majordomus-cli/Cargo.toml --test mesh_cooperation

Evidence required

• vacant_seat_is_taken

Evidence

None recorded. Every token above needs a command or an artifact behind it before this issue can be completed; narrative is refused.

Timeline

started

—

verified

—

completed

—

Those three fields, the evidence above and the state of the dependencies are all the status is made of. There is no status field to disagree with them.

Canonical record: .ai/repo/project/issues/I3912.yaml. Read it back with majordomus plan show I3912.