fix(web): generate model-backed session titles

packages/session-title/session-title-llm/README.md

@@ -8,7 +8,7 @@ This package is a library, not a Cordis plugin. The provider plugins call `regis
 
 `provider` and `model` overrides are optional but must be supplied together as non-empty strings. Without that pair, the helper uses the exact provider/model route captured from the current session's logged `request/header`; an explicit refresh before any route exists therefore needs overrides. The helper measures the final JSON-framed user prompt, including seq fields, wrappers, and JSON escaping, against `maxInputBytes` before logging or dispatch instead of truncating it. Timeout and caller cancellation are rechecked while consuming the stream and after it completes, so a late successful result cannot be accepted even if an interceptor or adapter ignores abort. Malformed or empty output, tool calls, and non-stop finish reasons also reject; the session-title service decides whether that rejection is an automatic warning or an explicit caller failure.
 
-After route and input validation, the helper appends a log-only `session/title-llm-request` event before model dispatch. It contains the title-provider id, exact source seqs, route, system prompt, message list, and output-token cap used by the call. The append shares the title capability's per-session settlement queue, so a superseding request cannot collide with an earlier fallback, request record, or accepted-title flush. The dispatched envelope is deep-frozen to keep interceptors aligned with that record but deliberately lacks dsh-agent-loop's process-local request identity, so loop-only reconstruction observers do not compare it with the conversation header. A later model failure leaves that request record intact; validation failures that never become dispatchable requests do not create one. The event stays outside derived model history.
+After route and input validation, the helper appends a log-only `session/title-llm-request` event before model dispatch. It contains the title-provider id, exact source seqs, route, system prompt, message list, and output-token cap used by the call. The append shares the title capability's per-session settlement queue, so a superseding request cannot collide with an earlier fallback, request record, or accepted-title flush. The dispatched envelope is deep-frozen, carries `purpose: 'session-title'`, and deliberately lacks dsh-agent-loop's process-local request identity. Interceptors stay aligned with the record while loop-only reconstruction observers do not compare it with the conversation header. The DeepSeek adapter maps that purpose to thinking-disabled so the small output budget is reserved for visible title text; other adapters own their purpose-specific behavior. A later model failure leaves the request record intact; validation failures that never become dispatchable requests do not create one. The event stays outside derived model history.
 
 ## Configuration
 
@@ -33,7 +33,7 @@ The title model receives a fixed system instruction to return one concise unador
 
 #### Token effect
 
-The auxiliary request consumes tokens according to selected input size and `maxOutputTokens`. It is separate from the main agent request and does not add title text or framing to agent history.
+The auxiliary request consumes tokens according to selected input size and `maxOutputTokens`. It is separate from the main agent request and does not add title text or framing to agent history. DeepSeek title calls disable thinking; the main conversation retains its configured thinking mode.
 
 #### KV Cache effect
 

packages/session-title/session-title-llm/src/index.ts

@@ -261,6 +261,7 @@ export async function generateSessionTitleWithLlm(
     system,
     maxTokens: config.maxOutputTokens,
     sessionId: request.session.id,
+    purpose: 'session-title',
     signal: callDeadline.signal,
   })
   await appendSessionTitleOutOfBand(ctx, request.session, 'session/title-llm-request', {

packages/session-title/session-title-llm/tests/llm.spec.ts

@@ -156,6 +156,7 @@ describe('generateSessionTitleWithLlm', () => {
       model: 'current-model',
       maxTokens: 32,
       sessionId: providerRequest.session.id,
+      purpose: 'session-title',
     })
     expect(options.system).toContain('5 words')
     expect(options.system).toContain('10 CJK characters')