Session Titles
Durable latest-wins title state and the optional asynchronous provider vocabulary owned by @deepseek-ai/dsh-session-title. The shared LLM helper owns the exact auxiliary request record. Package READMEs own timing, fallback, failure, and fork behavior; the generated persistence catalog owns the complete event declarations.
Sources: packages/session/session-title/src/index.ts, packages/session/session-title-llm/src/index.ts
Durable title state
SessionTitleProviderId is recorded for provider-produced revisions. SessionTitleEventData lists the exact human-message seqs used for the title, while SessionTitleSnapshot adds the durable event envelope facts selected by foldSessionTitle().
/** Identifies one session-title provider registration. */
type SessionTitleProviderId = Branded<'SessionTitleProviderId'>/** Exact auxiliary model route that produced a title. */
interface SessionTitleModelProvenance {
/** Registered LLM provider route. */
readonly provider: string
/** Provider model id. */
readonly model: string
}/** Durable ownership record for an accepted session title. */
type SessionTitleSource =
| { readonly kind: 'fallback' }
| {
readonly kind: 'provider'
readonly provider: SessionTitleProviderId
readonly model?: SessionTitleModelProvenance
}
| {
/** Explicit user rename: pins the title — automatic generation stops scheduling. */
readonly kind: 'user'
}/** Payload of the log-only `session/title` event. */
interface SessionTitleEventData {
/** Normalized non-empty title text. */
readonly title: string
/** Exact human `user/message` seqs used to derive this title; empty for an explicit user rename. */
readonly messageSeqs: number[]
/** Whether the built-in fallback, a registered provider, or the user supplied the title. */
readonly source: SessionTitleSource
}/** Latest folded title plus the title event's durable envelope facts. */
interface SessionTitleSnapshot extends SessionTitleEventData {
/** Seq of the latest `session/title` event. */
readonly eventSeq: number
/** Timestamp of the latest `session/title` event. */
readonly updatedAt: number
}Auxiliary request record
The shared LLM helper records each validated, dispatchable title request before calling the model. The payload reproduces the model-visible system and message input, routing, output limit, provider ownership, and source-message attribution even when generation later fails.
/** Exact model-visible request recorded before one auxiliary title dispatch. */
interface SessionTitleLlmRequestEventData {
/** Registered title-provider identity responsible for the request. */
readonly titleProvider: SessionTitleProviderId
/** Exact human `user/message` seqs represented in `messages`. */
readonly messageSeqs: number[]
/** Exact auxiliary LLM route. */
readonly route: SessionTitleModelProvenance
/** Exact auxiliary system prompt. */
readonly system: string
/** Exact auxiliary message list. */
readonly messages: Message[]
/** Exact auxiliary output-token cap. */
readonly maxTokens: number
}Provider input and output
The service snapshots eligible messages through one revision. A provider returns only seqs from that request; service-owned acceptance verifies ordering, normalizes the title, enforces the byte limit, and appends the title with its source-message seqs and source kind.
/** One eligible human text message exposed to title providers. */
interface SessionTitleUserMessage {
/** Source `user/message` event seq. */
readonly seq: number
/** Exact concatenated text-block content. */
readonly text: string
}/** Automatic generation cadence owned by a registered provider. */
type SessionTitleAutomaticMode = 'first-prompt' | 'all-prompts'/** Immutable input supplied to one title-provider call. */
interface SessionTitleProviderRequest {
/** Live session being titled. */
readonly session: Session
/** All eligible human messages through this generation revision. */
readonly messages: readonly SessionTitleUserMessage[]
/** Exact current logged main-request route, when one has been recorded. */
readonly route?: SessionTitleModelProvenance
/** Cancellation for supersession, disposal, timeout composition, or the explicit caller. */
readonly signal: AbortSignal
}/** Provider output before service-owned normalization and log acceptance. */
interface SessionTitleProviderResult {
/** Proposed title text. */
readonly title: string
/** Exact seqs from `request.messages` used by this result. */
readonly messageSeqs: readonly number[]
/** Auxiliary LLM route, when generation used a model. */
readonly model?: SessionTitleModelProvenance
}/** One optional asynchronous title implementation registered with the service. */
interface SessionTitleProvider {
/** Stable id of the provider recorded with the title. */
readonly id: SessionTitleProviderId
/** When new human prompts start automatic generation. */
readonly automatic: SessionTitleAutomaticMode
/**
* Produce one title revision.
* @param request - message snapshot, current route, session, and cancellation.
* @returns proposed title plus exact input seqs and the optional provider/model route used to generate it.
*/
generate(request: SessionTitleProviderRequest): Promise<SessionTitleProviderResult>
}Cordis API
Generated from source by scripts/gen-cordis-catalog.ts (verified fresh by pnpm run verify-cordis-catalog in doc-sync; regenerate with pnpm run gen-cordis-catalog) — this section is byte-identical in both language sides of the page. Signature blocks use a ts cordis-catalog fence and keep the original source JSDoc; dispatch modes are defined in the primer, and the framework-inherited ctx API lives in cordis-api/inherited.md.
ctx.sessionTitle — SessionTitleService
Log-backed title fold plus asynchronous fallback generation.
/**
* Read the latest folded title from one live or replayed session.
* @param session - session whose log is the title source of truth.
* @returns latest title snapshot, or `undefined` before eligible input.
*/
get(session: Session): SessionTitleSnapshot | undefined
/**
* Accept an explicit user title. Appends a `session/title` event with the
* `user` source, which pins the title: in-flight automatic generation is
* superseded and later user messages schedule none (an explicit
* {@link SessionTitleService.refresh} remains the deliberate unpin).
* @param session - exact live session to rename.
* @param title - raw user input; normalized before acceptance.
* @returns the accepted title snapshot.
* @throws {SessionTitleInvalidError} when the title normalizes to empty.
* @throws {Error} when the session is not live or the service is disposed.
*/
rename(session: Session, title: string): SessionTitleSnapshot
/**
* Explicitly retry the registered provider, or materialize the built-in
* fallback when no provider is registered.
* @param session - exact live session to refresh.
* @param signal - optional caller cancellation.
* @returns latest accepted title, or `undefined` when no eligible text exists.
*/
async refresh(session: Session, signal?: AbortSignal): Promise<SessionTitleSnapshot | undefined>
/**
* Register the sole optional title provider. Disposal aborts its pending and
* active work before another provider may register.
* @param provider - provider identity, cadence, and generation function.
* @returns exact Cordis effect disposer, which settles after active calls quiesce.
*/
register(provider: SessionTitleProvider): () => Promise<void>Types: Session