# 0.5.0 — History Recall and recoverable Session Rebase

Coordinated stable release of `ds4-context-core`, `ds4-context-reference-adapter` and `ds4-context-engine`. Both adapters depend exactly on `ds4-context-core@0.5.0`; Pi compatibility remains 0.84.3 and Node remains >=22.19.0.

## Changes

- Explicit `context_history_recall`, `context_history_read` and `context_history_status` tools reuse DS4's canonical session index and exact/FTS retrieval. Branch/type/date/role filters apply before SQL LIMIT; summaries and trusted project scope require explicit permission.
- Bounded original-source reads verify canonical byte locations and SHA-256. Opaque references expire and are reauthorized. Historical content remains quoted evidence, with privacy checks at tool and provider egress; recall output and queries are not recursively re-indexed.
- Manual `/context rebase --dry-run`, `/context rebase` and `/context rebase --recover <operationId>` use deterministic bounded checkpoints, verified lineage, canonical target staging, an inter-process lock and recoverable journal. Recovery validates the staged target prefix before activation; the original session is never deleted or truncated.
- Curated memory/pins carry forward with original provenance, existing mutation/confirmation requirements and continuation lifecycle overlays. SQLite migrations 17–18 add rebuildable source-locator, checkpoint, lineage and operation projections.
- **History Recall and Session Rebase are enabled by default**, as explicitly requested by the user. Configure or disable them through Pi's `/context config set historyTools.enabled false` and `/context config set sessionRebase.enabled false`; saved settings apply at the next session start. Existing explicit overrides take precedence. Rebase never runs automatically or as a model-callable tool.

## Scope and limitations

- No session-generation provider calls are needed for recall or rebase. Source data and crash tests use isolated synthetic sessions; existing user sessions/settings are not changed by release preparation.
- The default recall scope remains `current-branch`. Use explicit `current-lineage` scope to search verified ancestors after rebase; project-scope permission remains off by default. Rebase reduces the active session, not total archive/storage size.
- A handoff that exceeds the checkpoint budget fails closed rather than inventing a summary. Windows crash/filesystem behavior has not been executed on this Linux host.
- Semantic retrieval, `chars-v1`, BPE, auto-tuning, compaction validation and native continuation defaults are unchanged. The separate real-context BPE/auto-tuning objective remains unverified; synthetic tests do not complete it.
- Details: [feature contract](../HISTORY_RECALL_REBASE.md), [implementation record](../HISTORY_RECALL_REBASE_IMPLEMENTATION.md), [ADR 074](../ADR/074-canonical-history-recall-and-recoverable-session-rebase.md).

## Validation

On final 0.5.0 source after the acquired-policy reload:

- `npm ci` completed successfully on supported Node 22.23.1.
- `jev_verify all` passed node-typecheck, the complete node-test scope and git-diff-check after installation. This includes canonical recall/scope/privacy/budget tests, compatibility goldens, subprocess crash recovery at every rebase boundary, target-corruption rejection, inter-process lock recovery and the installed Pi 0.84.3 offline spike.
- `npm run quality:compare` completed successfully.
- `npm run schema:context-persistence` passed: 1,266 bytes / 317 estimated tokens; the existing memory-tool schema remains unchanged.
- `npm run pack:check` passed on Node 22.23.1: core 275 files, reference adapter 7 files, Pi extension 135 files, all exercised in a clean consumer.

The Windows and additional Node CI matrix were not executed locally. Subsequent publication-record edits are documentation-only; reuse the source/behavior results only while code, tests, dependencies and configuration remain unchanged.

## Publication and registry verification

Published manually to npm on 2026-10-05 by `alucard_24`, in dependency order:

1. `ds4-context-core@0.5.0`
2. `ds4-context-reference-adapter@0.5.0`
3. `ds4-context-engine@0.5.0`

All publication commands succeeded. Initial fresh-cache registry checks returned `ETARGET` for the newly published core; a delayed fresh-cache `npm run registry:check -- 0.5.0` then verified all three exact artifacts on Node 22.23.1. Separate `npm dist-tag ls` checks confirmed `latest: 0.5.0` for every package.

The annotated `v0.5.0` tag was created at release-preparation commit `7ee50a9` and pushed to origin after registry verification. [GitHub Release v0.5.0](https://github.com/Alucard24/ds4-context-engine/releases/tag/v0.5.0) was created from that verified tag. CI remains validation-only with no publishing credentials.