Session titles are never generated for sdk-ts sessions (only the first prompt is forwarded)

[rkage]

Session titles are never generated for sdk-ts sessions (only the first prompt is forwarded)

Running Claude Code through this adapter in Zed, thread titles always show the first user prompt rather than a generated summary. The same account/model via claude --resume on the CLI shows proper titles, so it's not the model or proxy.

The cause is that title generation only runs in the interactive CLI. For SDK-hosted sessions (entrypoint: sdk-ts, i.e. this adapter) the SDK doesn't auto-generate a title — it only generates one when the host explicitly sends the generate_session_title control request. The adapter never sends it, so getSessionInfo().summary stays as the first-prompt fallback, and that's what maybeUpdateSessionTitle() forwards.

#383 added the session_info_update forwarding on the assumption that session.summary is already an SDK-generated summary. That holds for CLI sessions but not SDK ones, so the forwarding works but there's nothing real to forward.

Evidence from my local ~/.claude/projects/<proj>/*.jsonl, correlating entrypoint with the presence of a "type":"ai-title" record:

• cli sessions: all have generated titles
• sdk-ts sessions (this adapter): 0 have them

And generate_session_title doesn't appear anywhere in src/.

The SDK exposes generation as a method on the query object:

generateSessionTitle(description, { persist }) // => Promise<string>

Proposed fix: in maybeUpdateSessionTitle(), if getSessionInfo() returns no customTitle/aiTitle, call generateSessionTitle(firstPrompt, { persist: true }) and forward the result via the existing path. It persists as a durable record, so it's one-shot per session, not per-turn.

Worth gating to interactive sessions so headless/CI SDK users don't get a title model-call on every run — which is likely why the SDK leaves generation to the host in the first place.

(#819 is manual rename — related but separate. Minor aside: generateSessionTitle is on the runtime query object but missing from the Query interface in sdk.d.ts.)

Env: adapter 0.58.1, claude-agent-sdk 0.3.205, Zed, macOS arm64.