session: auto title generation stopped in 2.1.4 - sessions stay untitled, no rename endpoint #58504

Summary

Since updating to opencode v2.1.4, automatic session title generation no longer runs. Sessions are created with an empty title and keep the client-side fallback ("New session - "). Data from my database shows a hard version boundary unaffected by config: ~60 sessions across v1.18.x–v2.0.32 were all auto-titled, and 8 of the 15 sessions created on v2.1.4 (installed today, 2026-10-23) remained untitled. The failure is silent — no error is surfaced and, unlike earlier versions, the log no longer shows any title-agent activity (agent=title stream events stop entirely after the update).

Environment

• opencode version: 2.1.4 (regression appeared exactly with 2.1.4; body from the previous release, 2.0.32, auto-titled fine)
• OS: Windows_NT 10.0.26200 (win32 x64)
• Terminal: Windows terminal host, TERM=xterm-256color
• Shell: cmd.exe host (commands run via PowerShell)
• Install/channel: npm-managed install, latest
• Active plugins: superpowers (git: https://github.com/obra/superpowers.git)

Model context: all sessions run on the built-in free provider models (opencode/*-free, e.g. opencode/glm-5.3-flash-free, opencode/deepseek-v4.1-flash-free). No Console account/credits configured. Under 2.0.32 the title agent streamed with a small free model (log: providerID=opencode modelID=muse-spark-1.3-contributor-free small=true agent=title) and titles appeared correctly.

Reproduction

1. Update opencode 2.0.32 → 2.1.4 on Windows
2. Start a new session in the TUI (or opencode run)
3. Send any message (verified reproducing with successful chats on opencode/deepseek-v4.1-flash-free)
4. Observe the session list: the session stays "New session - "; in the database (~/.local/share/opencode/opencode.db, table session_v2) title remains empty

Reproduces consistently (4 independent test sessions, TUI and run, including chats that succeeded normally).

Expected Behavior

The background title agent generates a title after the first user message, as in ≤ 2.0.32, and the session gets renamed.

Actual Behavior

No title generation occurs on 2.1.4:

• session_v2.title stays empty for all successful sessions after the update
• The server log contains zero title-agent events after the update (previously message=stream ... small=true agent=title lines and occasional "stream error" fallback entries existed for every session)

Version-boundary evidence from my local database (session_v2.grouped by version):

(The 2.0.32-era untitled entries are edge cases: failed/aborted sessions; the 8 untitled under 2.1.4 include fully succeeded TUI and opencode run sessions.)

Additional Context

Workarounds attempted per config, none restored auto-titling on 2.1.4:

{
  "small_model": "opencode/glm-5.3-flash-free",
  "agents": {
    "title": { "model": "opencode/glm-5.3-flash-free" }
  }
}

(small_model is documented in the V2 schema as "Small model to use for tasks like title generation". Both keys hot-reload confirmed via config.updated events in the log; new sessions still untitled.)

Possibly related API drift on 2.1.4: the published HTTP API documents POST /api/session/{sessionID}/rename (v2.session.rename), but the running 2.1.4 server returns 404 for that path, and its OpenAPI surface lists PATCH /api/session/{sessionID} (session.update) instead. opencode api patch /api/session/{id} --data '{"title":"..."}' returned InvalidRequestError: Expected a valid JSON body, and no opencode session rename CLI subcommand exists (only list/delete/export/import). So sessions with failed titles currently cannot be renamed from the CLI at all; I had to apply renames through the available runtime bindings.

Possibly related issues: #39532 (titles optional until generated or set), #13710, #29734, #30662 (silent auto-title failures; teammate closed as upgrade-to-2.0, but the regression now reproduces on 2.x).

Happy to provide opencode.log excerpts (redacted) or a heap snapshot if useful.