Preserve the V3 system-prompt projection while adopting master’s per-agent frozen-message provenance and frontend performance gates. Keep benchmark workload admission and diagnostics fixes intact, and retain both migration and first-open/reopen lifecycle guarantees.
Seed the request surface watermark from the attached session so a replacement before the first resumed request consolidates retained prompt versions. An unchanged resume still continues the series. Actual-loop replacement regression fails before the fix; 53 focused tests and the agent-loop project typecheck pass.
Use the same logged per-node normalization for an empty rendering as for incapable routes and broken request series: empty each active later system node, then empty the first node. Clearing only the latest node exposes stale earlier instructions, including converter-demoted user text. Dormant empty tails neither override effective text nor produce repeated replacements.
Keep the cleared structural head and ordinary restoration semantics: a capable continuing series may append new nonempty instructions, while incapable or broken-series requests refill the head. No initial empty-head creation change, deletion event, or rollback machinery.
Tests: capable/plain clearing after three active prompt versions fails before the fix and passes afterward; repeated clear and seeded resume remain empty without duplicate system events, restoration includes only new instructions, pi-ai conversion has no stale prompt, and source-event replay reconstructs every request. Final 395 loop tests pass with exact agent.ts/runtime-context.ts coverage at 100% all metrics; source tsc and focused lint pass. Fix new test discriminant narrowing discovered by focused compiler audit. Update EN/ZH consumers and owning rationale, seven pairs verified; parent owns broad gates and generated catalog/SDK/GUI updates.
Every same-step attempt resolves its bound route and reconciles the accepted rendered prompt against the current surface before deriving history. Preserve assembly, pre-step admission and entered users exactly once; compaction retries must not resurrect an older surviving prompt.
Normalize a broken request series to the current head plus dormant empty later system nodes, even if later versions survive or the effective text is unchanged. This removes the later-survivor exception without a delete operation and avoids appending instructions after already-admitted users on retry. Capture surface generation after reconciliation so subsequent ordinary retries do not emit phantom series headers.
Tests: both compaction cases fail before the fix (stale head, or stale later survivor), then pass with real loop/MockAdapter, pi-ai conversion and source-event reconstruction. Assert two retries keep one assembly/pre-step/user admission, preserve rendered text across section changes, and log one series boundary. Add unchanged-text explicit/tool series regressions. 391 loop tests with exact agent.ts/runtime-context.ts coverage pass at 100%; final admission spec has 11 passing cases. Source tsc and focused lint pass. Update EN/ZH implementation and owning rationale plus lifecycle retry documentation.
Resolve agent/request and prepareCall inside the accepted open step before committing system and user input. Preserve prompt-assembly model selection, bind capability and dispatch to the same prepared adapter, then log the envelope and derive the request synchronously. Preparation cancellation leaves a balanced empty step with no admitted input.
Normalize incapable-route retained prompt versions with logged per-node empty replacements and a current head, including unchanged rendering and resumed history. Dormant empty tails do not override the effective prompt. No new event or delete operation.
Tests: 389 agent-loop cases pass with exact agent.ts/runtime-context.ts coverage at 100% for all metrics; tsc -b packages/core/agent-loop/tsconfig.json passes. Seven actual-loop MockAdapter cases exercise pi-ai conversion, source-event reconstruction, both route transitions, resume, cancellation barriers, and bound selection. Stale-capability negative control fails all three transition regressions. Update EN/ZH request visibility, lifecycle generator, and owning rationale. Broad catalogs, recorded SDK/GUI and aggregate gates remain parent-owned.
Consolidate the existing in-history capability, loop, UI and artifacts into one baseline. Preserve the reviewed tree so each independently verified correction has a subsequent rationale-rich commit.
Cause: SystemPromptProjection skipped the first empty rendered prompt. The initial admitted user then occupied surface node zero, so a later nonempty prompt appended behind user history. Routes without in-history system support lost the leading system role; pi-ai demotes a non-leading system message to user content.
Fix: append the initial system node even when its content is empty. The existing loop commit order reserves node zero before admitted user messages; later prompt text replaces that node. Empty content still derives to no wire message. Keep retained-node replacement, clearing, multi-system handling, and pi-ai conversion unchanged; this addresses only the reviewed PR3476 initial-empty finding, not PR3483.
Tests: added initial-empty projection and two-turn loop regressions for empty wire output, reserved surface head, later leading system role, replacement intent, and series header. Negative control failed before the source fix. Focused projection/runtime-context/loop/request-reconstruction/session-surface/pi-ai-context suites passed 176 tests; exact runtime-context.ts coverage is 100% statements, branches, functions, and lines. test:docs passed all 15 gates. Updated README EN/ZH, architecture map and owning architecture note; recorded all three translation pairs. Broad doc-sync/lint stopped at parent request for combined-layer validation. No normalize.ts conflict-comment edit.
Consolidate the representation-change PR and its rebase reconciliations into one baseline. Preserve the exact tree and keep the in-history feature in the dependent PR. Follow-up fixes remain separate.
The persistence seam is now create/open/stat/list returning per-session
SessionHandles (read/append/flush/close); every log read and write flows
through the owning handle. The seam package exports only the service and
handle contracts, consumer-visible errors, and pure durable-data
validation helpers; each backend owns its complete storage runtime, and
the shared contract suites pin equivalent observable behavior. The
backend routes published sessions' live events by id into the active
write handle; agent-loop only acquires, seeds, and closes the handle.
Resume appends interruptedTurnClosers through its write handle;
session-query owns the revision-keyed cold cache. Legacy-only surfaces
are removed in the same swap: locate/readRaw/supportsRawArtifacts, the
legacy event-shape read migration, zstd torn-frame salvage,
DSH_SESSION_JSONL, and hook transcript_path population; a torn final
zstd frame is discarded whole; the session-list cold blank probe returns
on stat metadata (eventCount derived from the last physical row,
sizeBytes). The WebUI ZIP export serializes the logical log from a read
handle, so both backends export identically.
Refs #3245
Render reconstructable system prompts at each request-series boundary, preserve series declarations through pre-step wrappers, and keep the presentation and replay snapshots aligned across clients.