# Collaborative state awareness

Status: proposed mechanism, to be reconciled with the accepted foundation records.
No durable watcher service is introduced by this document.

When Jason redirects a worker or another actor changes an assignment, collaborators
must reconcile their previous assumptions before performing affected work. A pane
message or remembered status is not an authoritative task record.

## Proposed change contract

Record material changes with a stable subject identity, monotonic version, actor,
scope, event kind, evidence pointer, and concise description. Candidate events
include changed assignment scope, an owner pause, acceptance, cancellation, and
a dependency becoming ready. Keep private message content out of broad notices.

Authorized watchers retain their last reconciled version. Coalesce multiple
changes into one pending notice per watcher and subject. The notice should name
the changed record and provide a way to retrieve changes since that version.
Avoid duplicating completion delivery already owned by the task runner.

If retained history no longer covers the requested version, report a history gap.
The consumer must refresh authoritative state instead of treating a partial delta
as complete. Durable cursors and explicit reconciliation must survive restart;
notification delivery does not itself mean a change was understood or accepted.

## Required distinctions

Optional awareness notices may degrade visibly. Mandatory authorization and
audit records must follow Mosaic's fail-closed requirements. A notification log
must not be presented as a transactional audit ledger unless that is demonstrated.

Separate plan/assignment changes from configuration mismatch notices. Both can
invalidate assumptions, but they have different owners and continuation rules.
A watcher learns only information it is authorized to see.

ACT-C04 tests interpretation of synthetic events. Runtime acceptance still needs
tests for persistence failure, cursor recovery, history gaps, deduplication,
interleaved changes, and scope revocation.

See [session attachment](session-attachment.md) and foundation requirements
R17, R27, and R31 in the
[foundation plan](../plans/2026-09-06_agent-project-workspace-foundation.md).