2026-07-30 15:32:06 +08:00
# Agent Note: the end-seed log boundary
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
Status: implemented
2026-07-30 15:32:06 +08:00
English | [中文 ](2026-07-30-session-end-seed-log-boundary.zh.md )
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
## Problem
2026-08-13 00:36:22 +08:00
A plugin that owns a standalone open/close bracket in the session log cannot tell a dead marker from a live one. `compaction/start` … `compaction/end` is the shipped case: on picking up a log whose last compaction event is an unmatched `compaction/start` , "the previous writer died mid-compaction" and "a compaction is running right now" are byte-identical stored history. The owner must either refuse to compact a log that is actually free (wedging the session) or proceed over one that is genuinely busy.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
Nothing in the log marked where inherited history ended. `session/created` , `session/disposed` , and `session/flush` are cordis runtime signals, not log events; `agent/session-start` is emit-only. `Session.firstLiveSeq` already held the answer exactly — the seq of this lifecycle's first own write — but only in memory, so a consumer reading stored bytes could not see it.
2026-08-13 00:36:22 +08:00
Crash repair does not close the gap and must not: `interruptedTurnClosers` synthesizes turn, step, and tool boundaries because core owns that vocabulary, and `compaction/*` belongs to the compaction seam. A core repair pass that closed plugin brackets would put every plugin's bracket semantics in core.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
## Decision
2026-07-31 13:24:30 +08:00
`Session` 's constructor appends the log-only `session/end-seed` event immediately after an explicitly supplied constructor seed, including an empty one, as the seeded session's first live write at the seq `firstLiveSeq` names. The event is the durable projection of that field: `firstLiveSeq` answers where this lifecycle's writes start for a consumer holding the object, while `session/end-seed` answers the same question for one holding only stored bytes. Its payload is empty — position and `time` carry the whole meaning — and it is not a `SurfaceEventType` , so it produces no message and cannot perturb derived history. The seq-0 marker distinguishes an empty resumed session from a genuinely fresh session, preventing new-session defaults from being applied during resume.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-07-30 15:32:06 +08:00
A bracket owner reads it positionally: an unmatched opening marker before `session/end-seed` has a smaller seq, came from the constructor seed, and belongs to a lifecycle that has ended. Core writes the boundary and reads nothing from it; each bracket's vocabulary stays with its owning plugin, so no core predicate helper ships without a consumer to shape it.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-08-13 00:36:22 +08:00
The constructor is the placement because it is the single waist every seeded session passes through. All six entry points reach it: `agents.resume()` , config-driven startup on a persisted id (`restoreOrCreateConfigured` ), `sessions.fork()` , a subagent fork child, `coordinator.adopt()` 's live-prefix path, and a bare `sessions.create(id, {seed})` . A boundary written at persistence load would miss both fork paths — and a forked child inheriting a still-running parent's open `compaction/start` is precisely the case that must be classifiable. A boundary written at loop start would miss `fork()` and `adopt()` , and would have to fire on `SessionStartSource: 'startup'` , which is what a fork child publishes, so that field would stop discriminating.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-07-31 22:48:30 +08:00
Two guards keep the marker precise. An omitted seed writes nothing because the session is fresh. A seed already ending in one is not re-marked, which makes the write idempotent. Idempotence is load-bearing rather than tidiness: each Agent-bound pickup of a cold session passes through `agentFor()` , and without the guard repeated controls would grow the log even when they perform no work. The inspection-only `session.history` and `session.fork` source paths do not create this boundary in the source.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
## Persistence needs no changes
2026-07-30 15:32:06 +08:00
The constructor append happens before `enter()` , so the session has no store attachment: the marker never publishes on `session/event` , exactly like the seed events before it. It is instead part of the log `initFor` captures as the creation seed, and persists through the ordinary seed path — `onCreated` 's `createCore` + `appendCore` , or the ownerless-claim suffix write. A consumer that watches the firehose therefore never sees the boundary and must read it from the log.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
fix(session): close the review gaps the boundary opened
- `SessionSummary.updatedAt`'s wire doc still said "Persisted file mtime",
which stopped being true for attached sessions.
- The core invariant let `session/inherited` fall through the merge-extensible
default. It is core-owned, so it gets an explicit case; an unbalanced seed
legally places it inside an open turn, which the relation permits.
- The Agent Note claimed the boundary reaches disk via `live.pending`/
`scheduleDrain`. Verified false: the constructor append precedes `enter()`,
so it never publishes on `session/event` and rides the creation seed instead.
Attaching is therefore a write where none happened before — recorded, since
only `load()` stays a pure read.
- The deferred-index proposal asserted this change documented the cold-mtime
skew on `dsh-host-apiproxy`. It did not; the README entry now exists.
- `firstLiveSeq`'s firehose gap runs through its own seq, not below it.
- The boundary is not always at `firstLiveSeq` (the idempotence guard), so
consumers scan for the last one.
- `lastActivityTime` excludes by type, so a pickup time still leaks onto a
synthetic closer when a boundary ends an open turn. Documented.
- Pin the fork claim end-to-end: a child inherits a still-running parent's
open bracket below its own boundary, while the parent has none. Fails if the
write moves back to the load path.
- Fix the telemetry title that contradicted its own assertions.
The `/status` call site cannot be pinned the way the other two are: the
command appends its own `command/run` before rendering, so the boundary is
never the log tail there. Its fixture now at least renders over a
boundary-bearing log.
2026-07-30 13:59:08 +08:00
Consequences for the seam: `load()` stays a pure read, with no revision bump, no `commitRepair` on a balanced log, and no durable mark left by a rejected `append` . **Attaching is not a pure read** , though — a pickup now writes where nothing was written before, so a read-only or full disk fails at `session/created` rather than at the first real turn. That is the one cost this placement adds, and it is narrower than the load-path version's (which failed the load itself).
2026-07-30 15:32:06 +08:00
A crash before the seed write reaches disk loses the boundary, and that costs nothing: the pending batch is written in order, so a lost boundary means every event after it is lost too. The next pickup reads the same bytes the previous one did, appends its own boundary, and classifies the bracket identically. In-process consumers should prefer `firstLiveSeq` , which is exact before any write.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
## Scope of the guarantee
The predicate holds for a bracket *this* session inherited, not as a liveness signal about other writers. A concurrently live session may hold an open bracket over the same stored history while its own boundary sits elsewhere. A consumer that must tolerate concurrent writers needs a liveness signal beyond the log and cannot omit it on the strength of this event.
## Alternatives considered
docs: purge chain-of-thought leakage from prose
Delete design-session citations (decision/audit/plan ordinals, stack
positions), change narration, review choreography, and reviewer-addressed
justification from comments, JSDoc, docs, READMEs, Agent Notes, tests, and
generator templates; restate every affected fact as current-state contract
prose. Fix generated docs at their sources and regenerate the catalogs and
cordis-surface regions; re-paste type-equiv blocks; update every bilingual
counterpart and re-record the pairs. Record the citation rule in the
committed-artifact-citations Agent Note.
2026-08-09 15:09:19 +08:00
**A boundary written by the persistence coordinator's cold-load path.** An earlier iteration wrote a `session/resumed` boundary; it lost because it covers no fork — the one case where the inherited bracket's owner may still be running — and because a marker minted at load had to be a durable write on a read path, which spread cost across the seam: a revision bump on every cold load, a `commitRepair` batch on a balanced log with nothing to repair, a stored-time floor to keep the clamp monotonic, and a load that failed against a read-only store.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-07-30 15:32:06 +08:00
**A boundary appended at loop start.** The loop calls `resumeWith` , so it covers the resume paths, but it misses `fork()` and `adopt()` entirely, and the event would have to fire on `'startup'` — the source a fork child publishes — so `SessionStartSource` would stop discriminating. It also publishes the session before the marker is appended, so a `session/created` listener could observe a seeded log with no boundary.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-08-31 03:10:27 +08:00
**Reusing `Session.inheritedEventCount` .** It is the durable *fork-lineage* cut and deliberately keeps the original fork value across a resume, where the constructor seed is the whole stored log. The two facts differ and conflating them would lose both.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-08-13 00:36:22 +08:00
**Crash repair closing `compaction/*` alongside turn boundaries.** Rejected: it moves every plugin's bracket semantics into core's repair pass, and core cannot know what closing another package's bracket should record.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
## Consequences
2026-07-30 12:01:45 +08:00
Bought: one boundary, written in one place, correct for all six seeded-start paths — including the fork gap the persistence-layer version could not reach. The persistence packages keep a pure read path. `firstLiveSeq` gains a durable twin rather than a second, competing notion of the same boundary.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-07-31 13:24:30 +08:00
Cost: a seeded session's log is one event longer, including an empty resumed log. Seq expectations move with that boundary. Two updates are load-bearing rather than mechanical: telemetry's adoption tests assert the boundary IS exported, because it is this lifecycle's own write, and the property suite's replay invariant is "seed reproduced verbatim, plus one log-only boundary" with idempotence as its own property.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-07-30 15:32:06 +08:00
`session/end-seed` joins the on-disk vocabulary. Under the pre-release stance (`SESSION_FORMAT_VERSION` pinned at `0` , no compatibility promise) older logs simply lack it, and a log without a boundary correctly classifies nothing as constructor-seed history.
feat(session): project the inherited-history boundary into the log
A plugin owning a standalone open/close bracket cannot tell a dead marker
from a live one: an unmatched `compact/start` reads identically whether the
previous writer died mid-compaction or a compaction is running now.
`Session.firstLiveSeq` already holds that answer exactly, but only in memory.
Append the log-only `session/inherited` event at that seq from the seeded
constructor — the single waist all six seeded-start paths pass through
(resume, configured startup on a persisted id, `sessions.fork()`, a subagent
fork child, `adopt()`'s live prefix, and a bare seeded `create`). Read it
through the new `isInheritedSeq(events, seq)`.
The constructor placement means persistence needs no changes: the marker is
already in `events` when a backend captures the creation seed, so it rides
the ordinary seed path with no load-time write. It also covers fork, where
the inherited bracket's owner may still be running — the case a
persistence-layer boundary could not reach.
Activity ordering excludes the boundary through `lastActivityTime()`, since
lazy resume makes browsing a pickup and the three call sites would otherwise
float every opened session to the top of a picker or list.
2026-07-30 11:38:51 +08:00
2026-08-13 00:36:22 +08:00
The [queued manual compaction decision ](../feature/2026-07-30-queued-manual-compaction.md ) now supplies the first consumer. Its tail scan independently finds the unmatched `compaction/start` and newest end-seed, treats only a start after that boundary as live, and clears the invariant trace on the same replay transition. The predicate remains in the compaction package rather than becoming a generic core helper.
