Fleet spawn times out unconfirmed after worker is live and attachable

[kjgbot]

Reproduction (2026-09-22, broker 12.4.0)

Run a targeted, confirmed agent-relay fleet spawn codex --node sf-frame --name relay-delivery-gap-repair --cwd /home/khaliqgant/Projects/AgentWorkforce/relay --task ... from a pinned workspace. The node acknowledges invocation inv_228071519860695040, but the CLI waits the full 120000 ms and exits spawn_unconfirmed / unconfirmed_may_be_running with no result.

During that same wait, agent-relay fleet agent list --json already listed relay-delivery-gap-repair as a live, node-owned worker on sf-frame. agent-relay node agent attach relay-delivery-gap-repair --node sf-frame --mode view succeeded and showed it executing the assigned task. Do not retry blindly: that would duplicate work.

This is a confirmed-success reporting gap, distinct from a genuinely accepted-but-never-launched spawn. It appears related to the previously closed #1563 but persists on 12.4.0.

Acceptance

• A registered and attachable target worker yields a successful confirmed spawn result with spawned:true and ready:true proof (or equivalent), before the confirmation timeout.
• A broker receipt lost after registration can be reconciled against the exact invocation/name/node identity without accepting a different worker as proof.
• Deterministic integration coverage distinguishes live-and-ready, accepted-but-not-launched, and launched-but-unregistered; no false success and no false failure.
• The CLI and MCP surfaces report the same reconciled outcome and preserve retry safety.

[kjgbot]

Second confirmed false-negative targeted spawn: agent-relay fleet spawn claude --node dogpatch-mini --name babysitter-native-handler ... returned spawn_failed for invocation inv_228087382933995520 with receipt status:completed but no explicit spawned:true, ready:true. Immediately afterward, fleet roster showed dogpatch-mini 1/15 and live agent babysitter-native-handler. I did not retry spawn. This is the same completed-without-proof failure mode on a different node.

[kjgbot]

Additional reproduction on sf-frame (broker 12.4.0), 2026-09-22 10:37 UTC: fleet spawn codex --name babysitter-gate8-isolation --cwd /home/khaliqgant/Projects/AgentWorkforce returned spawn_failed because node reported completed without explicit spawned:true and ready:true proof (invocation inv_228102381856292864). Immediately afterward, fleet agent list showed babysitter-gate8-isolation as live on sf-frame. No retry was issued. A prior attempt with a macOS cwd failed correctly as worker_cwd not resolvable; this reproduction is the second, Linux-cwd attempt.