Function hook_cursor_pre_compact

src/hooks/cursor.rs:223–240

Cursor `preCompact` hook handler. Cursor's compaction event exposes pressure metadata but not Cursor's own generated summary text. At the boundary, `TraceDecay` ingests the current transcript tail, asks LCM for the compactable raw-message backlog, generates a summary through `cursor-agent -p`, and stores that summary as a normal LCM summary node. The hook is fail-open and emits Cursor's empty obj

()

/// a summary through `cursor-agent -p`, and stores that summary as a normal LCM
/// summary node. The hook is fail-open and emits Cursor's empty object shape.
pub async fn hook_cursor_pre_compact() -> i32 {
    let event = read_hook_event!();
    let root = cursor_project_root_from_event(&event);
    record_hook_invoked(root.as_deref(), HintAgent::Cursor, "preCompact", &event);
    if std::env::var(crate::sessions::cursor_agent::CURSOR_SUMMARY_CHILD_ENV).is_err() {
        let mut config = crate::sessions::cursor_agent::CursorAgentSummaryConfig::from_env();
        config.timeout = config.timeout.min(CURSOR_PRE_COMPACT_SUMMARY_BUDGET);
        let outcome = cursor_pre_compact_for_event_with_config(&event, &config).await;
        if outcome.status == "error" {
            eprintln!(
                "tracedecay Cursor preCompact summary failed: {}",
                outcome.reason
            );
        }
    }
    println!("{}", serde_json::json!({}));
    0
}

/// Cursor `afterFileEdit` hook handler.
///