zenmemes

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LLM Generated Thread Titles Plan

Goal

Generate helpful display titles for titleless threads asynchronously, without rewriting user-authored post content.

Product Rules

  • User-authored subject always wins.

  • Generated titles are metadata, not canonical authored content.

  • The deterministic body excerpt remains the fallback when no generated title exists.

  • Display precedence should be:

    1. User subject

    2. Approved/generated title

    3. Deterministic body excerpt

    4. Thread id fallback

Data Model

  • Add generated-title storage outside the canonical post record.

  • Store at least: thread_id, title, provider, provider_model, status, confidence, body_hash, created_at, updated_at, and failure details.

  • Keep generated title records idempotent by thread_id plus body_hash.

Worker Shape

  1. Add a script or command for cron execution, for example scripts/generate_thread_titles.php.

  2. Select titleless threads where:

    • subject is empty.

    • Body is non-empty.

    • No completed generated title exists for the current body hash.

    • No generation is currently in progress.

  3. Ask the configured LLM for a concise, neutral title.

  4. Validate output:

    • Non-empty.

    • Short enough for feed display.

    • No line breaks.

    • Passes the same authored text safety constraints used for subjects.

  5. Persist completed titles as metadata.

  6. Record retryable and terminal failures separately.

Rendering Integration

  • Extend the thread title helper to accept generated title metadata.

  • Update board, tag, profile, thread, API list, and RSS title paths to use the same precedence.

  • Keep canonical Subject: output unchanged in raw thread APIs unless explicitly adding a separate Generated-Title: field.

Tests

  • Unit-test title precedence.

  • Smoke-test titleless thread display with and without generated metadata.

  • Test stale generation when body hash changes.

  • Test provider failure does not break board/thread rendering.

  • Test user-authored subject overrides existing generated metadata.

Open Questions

  • Should generated titles be visible to everyone immediately, or only after approval?

  • Should approved users be able to reject or replace generated titles?

  • Should generated titles be materialized in the read model or loaded from a separate metadata store at render time?