Next release: thread lifecycle, storage and source control #535

Plan of record for the next release: a real thread lifecycle and T3 Code's source-control integration, ported wholesale. Source of truth for every spec below is T3 Code's current code (commit 83a82a46b, Oct 2026); the issues are rewritten in place whenever the facts change, never annotated with history. On delivery each issue is closed; superseded ones are closed as not planned.

Decisions

• Lifecycle: Settled is a real state with automatic settlement (inactivity after 3 days, linked PR terminal), exactly as upstream; idle auto-archive is removed; archive is always explicit. Pinned threads, with manual arrangement. Snooze is deferred. Settle detaches the provider session and closes idle terminals. Pinned threads are exempt from automatic settlement (upstream code, not its doc).
• Sidebar: root threads and forks only; dispatched and native-subagent children live under the parent's Agents view.
• Orchestrate: archive_on_complete and the archive tool are removed; the lead settles each dispatched child after accepting its result, and an unsettled child is not delivered.
• Message origin is recorded explicitly (human, agent, server) from B1 on; historical top-level messages are human, messages in child threads are model-dispatched.
• Source control: direct GitHub API with a header-driven quota ledger and a 10% background reserve (gh only for the token); durable thread ↔ PR links with batched sync and branch discovery; a host-owned PR watch that wakes the agent; five MCP tools with instructions injected visibly every turn; a complete PR client in Tcode's own model; GitHub native stacks in the data model from the start and stack actions later; media fetched by the host for the client; other hosts (Forgejo/Gitea, GitLab, Bitbucket, Azure DevOps) after GitHub is complete, by extracting the trait from the finished code. Policies, cadences, limits and TTLs are copied from upstream as-is. Two deliberate watcher deviations are recorded in Source control: pull request watch that wakes the agent (A3) #639.
• Storage (shipped in feat: keep thread metadata and event logs in a Turso database #594, feat: keep Tcode's data in ~/.tcode on every platform #601): Turso database, one host writer; remaining compaction items deferred.

Phases (one PR each, in order)

Track B: lifecycle

• Thread lifecycle: Settled as a real state, automatic settlement, idle auto-archive removed (B1) #526 B1 Settled as a real state, automatic settlement, message origin, idle auto-archive removed (merged in feat: make settled threads a lifecycle state #651; resolved Unarchived threads are re-archived by the next auto-archive sweep #515)
• Thread lifecycle: root-only sidebar, Agents view, and orchestrate settle replaces archive (B1) #637 B1 Root-only sidebar, Agents view, orchestrate settle replaces archive (merged in feat: Agents view, root-only sidebar and orchestrate settle (#637) #656)
• Thread lifecycle: pinned threads and manual arrangement (B2) #528 B2 Pinned threads and manual arrangement (merged in feat: pinned threads and manual arrangement #663)

Track A: source control

• Source control: GitHub API transport, credentials and settings (A1) #638 A1 (merged in feat: add GitHub transport and Source Control settings #647) GitHub API transport, credentials, quota ledger, Settings → Source Control
• Source control: linked pull requests, sync, branch discovery, stacks, and linking tools (A2) #532 A2 Linked pull requests, sync, branch discovery, stacks in data, linking tools (merged in feat: link and synchronize thread pull requests (A2) #652); PR rule in settlement and the merge-settle setting row (merged in feat: settle threads from linked pull requests #657)
• Source control: pull request watch that wakes the agent (A3) #639 A3 Pull request watch (merged in feat: watch linked pull requests and wake the agent (#639) #658)
• Source control: pull request client, read side (A4) #640 A4 PR client, read side, media (merged in feat: read a linked pull request in Tcode (A4) #664)
• Source control: pull request actions (A5) #641 A5 PR actions (A5a review and conversation merged in feat: pull request review and conversation actions (A5a) #666; A5b merge and lifecycle merged in feat: merge and lifecycle actions on a linked pull request (A5b) #667)
• Source control: GitHub stack actions, merge and rebase (A6) #642 A6 Stack actions: async merge, rebase (merged in feat: GitHub stack actions: async merge and rebase (A6) #672)
• Source control: other hosts, Forgejo/Gitea, GitLab, Bitbucket, Azure DevOps (A7) #643 A7 Other hosts

Later, not in this release

• Thread lifecycle: snooze (deferred) #527 Snooze
• Archive: align with the Codex app (log move, provider-native archive, undo) #529 Archive aligned with the Codex app
• Worktrees: host-owned ownership and an archive lifecycle (snapshot, transfer, keep-count) #530 Host-owned worktree ownership and archive lifecycle
• Providers: tie process lifetime to the prompt-cache TTL #531 Provider process lifetime tied to the prompt-cache TTL
• Startup orphan sweep force-removes worktrees the user chose to keep #516, Deleting a thread leaves its descendant threads with a dangling parent #518, Batch thread lifecycle commands instead of one index rewrite per thread #521 remaining Phase 0 items
• Storage compaction (Storage: compact thread logs at turn end #522, Storage: turn index so long threads open without parsing the whole log #524, Client: bound history memory for visited threads #525), re-evaluated on Turso

Closed as not planned

• Source control: Open PR action usable during a run, with merge when CI passes #533 Open PR action during a run (superseded: agents create PRs with their own tools and register them with link_pull_request; "merge when CI passes" is the auto-merge action in Source control: pull request actions (A5) #641)
• Source control: settle threads and clean up worktrees when linked PRs merge #534 Settle on merge and worktree cleanup (settle-on-merge is the PR rule in Thread lifecycle: Settled as a real state, automatic settlement, idle auto-archive removed (B1) #526 and Source control: linked pull requests, sync, branch discovery, stacks, and linking tools (A2) #532; worktree cleanup belongs to Worktrees: host-owned ownership and an archive lifecycle (snapshot, transfer, keep-count) #530 and is an independent sweep, not a settlement input)

Coordination

Wire changes note themselves under PROTOCOL_VERSION and are bumped once at the release (CONTRIBUTING Principle 9). Both desktop and headless composition roots mount the new MCP server and start the host sweeps. Every phase runs the full CONTRIBUTING checks plus the live checks named in its issue.