The tab (a chat) is the context unit: two opencode tabs in one session are two independent agent contexts sharing one worktree. agent_sessions re-keys from (session_id, agent) to (chat_id, agent) — chat_id FK ON DELETE CASCADE (closing a tab ends its context); worktree_id and session_id become informational SET NULL columns. New worktrees table (one-per-session, survives session delete via session_id SET NULL) supersedes session_worktrees, which is defanged (CASCADE dropped) not yet removed. chat_id is threaded end-to-end: tasks.chat_id added, written by the coder message + skills routes from the frontend tab, read by runOpenCodeServerTask which falls back to resolve-or-create a chat for session-less creators (arena/MCP/new_task/generic) so ensureSession never gets a null key. Idempotent migration with a backfill-verify gate (0-row assertion after the test session was deleted). config_hash fingerprint logic preserved; one-worktree-per-session unchanged; runExternalAgent untouched. Column rename worktree_path -> path repointed at all five readers (server delete-guard, risk/stash endpoints, ensureSessionWorktree). Supersedes the earlier (worktree_id) draft.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Replace the single global SSE loop (scoped to the most-recently-used worktree directory) with one subscription per live opencode session, each scoped to that session's worktree dir. Two sessions in different worktrees now stream concurrently instead of the second silently dropping the first's events. Each session owns an AbortController (SessionState.sseAbort) wired into subscribe(..., {signal}); the loop reconnects, reconciles (per-session), and is torn down on closeSession/dispose by aborting the signal — which also fixes a latent Phase-1 bug where switching directories left the old runEventLoop parked forever in its for-await (zombie loops). A sessionID demux guard (eventSessionId) drops events that aren't this loop's own, so two sessions sharing a worktree (possible after P1.5-b) don't double-process each other's deltas. Removed sseRunning/sseDirectory/startEventLoop/runEventLoop/reconcileInFlight and the 'SSE directory changed' collision warning. dispatchEvent/handleUpdatedPart (translation, dedup, dcp-strip) and the watchdog are unchanged — only the subscription topology changed. SDK confirmed: @opencode-ai/sdk Event.subscribe opens an independent SSE connection per call, so N concurrent dir-scoped streams are supported. No schema/dispatcher/frontend changes; runExternalAgent untouched.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Two independent fixes:
- opencode-server.ts: stripDcpTags() removes <dcp-message-id>…</dcp-message-id>
tags from text deltas before they reach the frame/DB. Applied to all three
text paths (session.next.text.delta, message.part.delta text field,
handleUpdatedPart text type). Reasoning/tool paths untouched.
- useWorkspacePanes.ts: module-level closedPaneStack (capped at 10) captures
pane kind + chatIds on removePane and removeTab auto-remove. reopenPane()
pops the stack and re-attaches a new pane to the existing chat ids (chats
survive pane close server-side). hasClosedPanes drives conditional render.
- ChatTabBar.tsx: [+] is now instant new-tab (no dropdown); split-pane
dropdown (Columns2 icon) opens Chat/Term/Code in a new pane; reopen button
(RotateCcw icon) appears when closed panes exist.
- Workspace.tsx: pass reopenPane + hasClosedPanes through to ChatTabBar.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
