kappa-techlead - Retrospective

What Went Well

Parallel generation architecture. Running 4 Lyria music stems simultaneously via background processes with self-message callbacks worked perfectly — all 4 completed in ~40 seconds wall time instead of ~8 minutes sequential.
Helper agent delegation. The qa-helper pattern for batch generation (kappa-dailies-helper) and mograph (kappa-mograph) kept my context window clean. I focused on prompt engineering and QA while helpers handled the noisy terminal output.
Character consistency fix for shot_10c. Identified that Clippy was rendering as a generic paperclip, regenerated storyboard frames with explicit character reference images (headshot + character_sheet), and the from-frames interpolation preserved the character design. The reference-chaining workflow in genmedia-image is powerful when used correctly.
Clean extend pass. All 6 extends landed at exactly 15.037s (8s base + 7s extension). The Veo 3.1 Lite extend model is reliable and consistent.
Team communication cadence. Batched status updates to coach, editor, and idea person at key gates. No wasted messages — every message carried actionable information.

Missed the extend requirement in the initial batch. Generated all 28 clips at 8s base without checking timeline-plan.md for planned durations. The 12s and 10s shots were physically too short. This was caught by the coach and editor, not by me — I should have cross-referenced the shot manifest’s extends field before declaring Step 5 complete.
shot_03 initial generation failure. The from-frames interpolation silently failed with “no videos were generated.” Root cause unclear — possibly the storyboard frame content triggered a safety filter or the interpolation couldn’t find a coherent motion path between the start/end frames. The helper retried it successfully, but the initial failure cost time.
kappa-extend-helper stall. The helper stalled after completing all 6 extends — it finished the shell command but didn’t process the result. Required manual intervention (stop + delete + verify). The stall was a platform issue, not a script issue.

Stall recovery. I was stalled at the start of this session (per coach message) and had to rebuild context from scratch — re-reading the brief, checking the dailies directory, understanding the generation log state. Having a persistent state file (e.g., dp-status.md) in the shared dir would have made recovery instant.
GCS upload latency for extends. Had to upload 6 clips to GCS before extending them. Each upload was ~2-3 seconds, but this is a serial bottleneck before the parallel extend could start. Pre-uploading all clips to GCS during the base generation pass would eliminate this.
Audit tool recursion. The genmedia-verify audit scans subdirectories, which caught backup _base8s.mp4 files after the extend pass. Had to move backups out of the dailies tree entirely.

Used from-frames (not reference) for shot_10c regen. Could have tried the reference subcommand with Veo 3.1 Preview for better character consistency, but from-frames with improved storyboard frames was the simpler, more predictable path. The result was good enough.
Sequential extends via script rather than parallel. Could have run 6 extends in parallel, but chose sequential to avoid potential API rate limits and simplify error handling. Total time was ~8 minutes — acceptable.
Lyria Pro for long stems, Lyria Clip for short. Used the 2:30 Pro model for the 90s and 50s music segments, and the 30s Clip model for the shorter montage/climax segments. All four had sufficient duration for the editor’s needs.
Delegated mograph to a helper. Title card and credits are low-risk, well-specified tasks — perfect for a helper. This freed me to focus on the music stems in parallel.

Pre-flight checklist before declaring a step complete. I should have had a mandatory checklist: “Does every clip meet its planned duration in the shot manifest?” before reporting Step 5 done. The extend pass requirement was clearly documented in the manifest — I just didn’t check.
Build the extend pass into the generation script. The generate-dailies.sh script should have a second pass that extends clips where planned > base_duration. This would make it a single-script execution instead of a two-pass process.
Persistent DP status file. Write a dp-checkpoint.md to the shared dir after each major milestone (storyboards done, base clips done, extends done, music done). This eliminates context rebuilding after stalls.
Upload-as-you-go pattern. Upload each clip to GCS immediately after generation so extends can start without a separate upload step.