chore(integrations): track upstream Tau continuity PR #687

[phernandez]

Purpose

Track our Basic Machines contribution to Tau and the downstream transition from the pinned fork to an upstream release.

Upstream PR: huggingface/tau#687
Title: feat: support awaited extension continuity across compaction
Status when filed: Open
Current downstream pin: basicmachines-co/tau@d8216af0b34059839734422d1e39b4c5972d7966

Required host capabilities

• Awaited extension callbacks for manual, detailed manual, threshold, and overflow compaction.
• Persisted active-branch entries for receipt reconciliation and lineage.
• Bounded tool-free synthesis through context.summarize.
• Idle reference insertion through tau.append_message without another agent turn.
• Shutdown/start lifecycle notifications for in-place branching.

The upstream PR replaces huggingface/tau#683. It addresses extension delivery related to huggingface/tau#506, not all frontend/TUI work in that issue. Compaction callbacks remain diagnostic-only, not a veto API.

Tracking checklist

• Monitor upstream review and address feedback in the Basic Machines Tau fork.
• Keep the downstream immutable pin and lockfile aligned with any required revisions.
• Confirm the upstream PR is merged and identify a published release containing all required APIs and the single-copy snapshot fix.
• Replace the fork dependency in integrations/tau/pyproject.toml and regenerate its lockfile against that verified release.
• Update the integration README, setup skill, and installer compatibility guidance; rebuild packaged resources.
• Run just package-check-tau, isolated real-BM continuity/schema tests, and the built-wheel installer smoke test against the upstream release.

Completion criteria

Close once Basic Memory uses a verified upstream Tau release and the downstream tests demonstrate compaction, reload/resume, branching, receipt reconciliation, and packaged installation still work. Upstream merge alone is not sufficient; retain the fork pin until the required APIs ship in a release.

Related work

• Basic Memory integration: feat(integrations): give Tau persistent Basic Memory continuity and full MCP tools #1487
• Initial continuity implementation: feat(integrations): give Tau persistent Basic Memory continuity #1489
• Shared schemas, setup, and packaged installation: feat(integrations): unify Tau memory schemas and setup #1493

[claude]

Claude finished @phernandez's task in 48s —— View job

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Triage

Type: Enhancement (tracking issue for an integration migration — moving from a pinned Tau fork to an upstream release once required continuity APIs ship).

Component: Integrations — integrations/tau (packaging, dependency pin, lockfile, setup skill, installer). Not a Cloud-specific issue, so no component:cloud label applied.

Priority: Medium — no user-facing breakage; work is gated on an external upstream PR (huggingface/tau#687) merging and shipping in a release, so it can't proceed faster than upstream.

Complexity: Complex — spans upstream review/feedback, dependency/lockfile updates, docs/skill/installer updates, and a multi-part test matrix (continuity, schema, packaged installer smoke test) once the upstream release lands.

Duplicate check: No duplicate found. Related and correctly cross-linked: #1487 (Basic Memory integration), #1489 (initial continuity implementation), #1493 (shared schemas/setup/packaging) — these are companion work items, not duplicates of this tracker.

Labels applied: enhancement.