Issue 8-025: Fix Diversity Cache Validation Order Bug

Current Behavior

Running ./run.sh --generate-diversity reports "Sequences to compute: 0" and generates an empty cache file, even when all embeddings are present.

Output shows:

📄 Poems: 7793
🧮 Embeddings: 7793 (dim=768)
...
🔢 Sequences to compute: 0

Root Cause

In scripts/precompute-diversity-sequences, the code flow is:

1. Line 377: embeddings_data = nil (release after building effil.table)
2. Line 388-402: Loop to build valid_poem_ids, checks elseif embeddings_data and ...

Since embeddings_data is nil by the time the validation loop runs, the condition on line 395 always fails in production mode:

elseif embeddings_data and embeddings_data.embeddings[i] and embeddings_data.embeddings[i].embedding then

Fix

Move the valid_poem_ids construction loop to run BEFORE embeddings_data is released (before line 376).

Secondary Issue: Thread Count Not Passed

run.sh exports DIVERSITY_THREADS but the script reads threads from arg[2]. Either:

• Add CLI argument passthrough in run.sh, OR
• Have the script read the environment variable

Files Modified

File	Change
scripts/precompute-diversity-sequences	Move validation loop before embeddings_data release
run.sh	Pass --threads to precompute-diversity-sequences

---

Phase: 8 (Website Completion)

Priority: High (blocking diversity cache generation)

Created: 2026-01-04

Completed: 2026-01-04

Status: Completed

Type: Bug Fix