Why: the loop now emits Last* and cache token usage; the product run
record needs the same fields for display and accounting (additive JSON,
old records deserialize as zero values).
Evidence: GOWORK=off go build + go test green.
Impact: additive only.
Refs: Agent-Native#35, N3 plan WP6
Why: Labeled secrets, excluded turns, and candidate replies need fields on the shared message contract, and context snapshots need a section breakdown plus a stable prefix hash.
Evidence: go test ./... in agent-system-core. New fields use omitempty, so existing golden JSON stays the same.
Impact: Clients that ignore unknown fields keep working. Assemblers can now mark a message excluded or as one candidate in a group.
Refs: docs/records/2026-10-04-sillytavern-review.md
Why: a fallback chain can answer with a different model than the one that was requested, and usage has to name the model that actually served.
Evidence: go test .
Impact: the field is omitted when empty, so existing usage JSON stays the same.
Refs: feature/durable-rewind
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: The product needs a session mode and a place to show tool arguments on a confirmation card without inventing a second card type.
Evidence: GOWORK=off go test . passed. New fields use omitempty, so existing golden JSON stays the same.
Impact: Empty permission mode still means the profile policy. Clients that ignore unknown fields keep working.
Refs: feature/permission-hooks
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: The final reply is composed after the work loop, and the automatic end check needs its own part and event so the timeline can show it without mixing it into the user-facing text.
Evidence: go test ./...
Impact: New RunPhase finalizing, PartType check, and run.check. Existing payloads are unchanged.
Refs: feature/final-reply-compose
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: The chat timeline needs a persisted thinking duration, and tool duration already lives on the tool call, so the thinking part had nowhere to put it.
Evidence: go test ./... passes; the message golden now includes durationMs on the thinking part.
Impact: Additive JSON field with omitempty. Existing clients ignore unknown fields.
Refs: feature/chat-timeline-preview
Co-authored-by: Cursor <cursoragent@cursor.com>
Why: cross-session transcript reading needs per-conversation outbound
(allowCrossRead, default true) and inbound (crossPrivate, default false)
flags alongside the project-level gate; see the approved proposal.
Evidence: go test ./... passes with golden conversation.json regenerated
to exercise both wire fields.
Impact: additive contract fields (omitempty), wire-compatible for
existing clients that ignore unknown fields.
Refs: Agent-System-Documents proposals/2026-09-30-cross-session-reading.md
(Dev task feature/cross-session-reading).
Why: the approved task-centric sidebar (proposal 2026-09-30, option A) needs
server-authoritative pin and archive state on conversations; client-side
storage would be fake state against the event-sourced model.
Evidence: go test ./... passes; omitempty keeps wire format and golden
samples byte-identical for zero values (backward compatible).
Impact: additive optional fields; consumers ignoring unknown fields are
unaffected (forward-compat principle). Backend consumes via submodule bump.
Refs: Agent-System-Documents docs/proposals/2026-09-30-ui-redesign-and-auth.md (P6/P8, R1)