threshold-change

name	threshold-change
description	Safe workflow for changing fuzzy-match threshold or OCR confidence cutoff values. Use whenever editing threshold/score_cutoff in core/item_actions.py or ocr/inventory_vision.py. Corpus replay required before shipping - see T001.
disable-model-invocation	true

Threshold Change

Changing the fuzzy-match threshold or OCR confidence cutoff affects every item match decision. A wrong value causes false positives (wrong action taken) or missed matches (items skipped). Corpus replay is required before shipping.

This is TODO T001 in the codebase. The hook in settings.json fires a warning whenever you edit a threshold constant.

Where the thresholds live

grep -rn 'FUZZY_THRESHOLD\|score_cutoff\|threshold' src/autoscrapper/core/item_actions.py
grep -rn 'threshold\|THRESHOLD' src/autoscrapper/ocr/inventory_vision.py

Both files share the same constant - change it in one place only.

Steps

1. Note the current value

grep -n 'FUZZY_THRESHOLD|score_cutoff' src/autoscrapper/core/item_actions.py

Record: before = <current_value>

2. Populate the corpus if empty

ls ocr_debug/

If empty, run a dry-run scan to populate it:

uv run autoscrapper scan --dry-run

The corpus must not be cleared between now and the replay. See the corpus-replay skill.

3. Run corpus replay at the CURRENT value (baseline)

uv run pytest tests/autoscrapper/core/test_item_actions.py tests/autoscrapper/ocr/ -v 2>&1 | tee /tmp/threshold_before.txt

Record pass/fail counts from the summary line.

4. Set the candidate value

Edit the threshold constant in src/autoscrapper/core/item_actions.py.

5. Run corpus replay at the NEW value

uv run pytest tests/autoscrapper/core/test_item_actions.py tests/autoscrapper/ocr/ -v 2>&1 | tee /tmp/threshold_after.txt

6. Compare

diff /tmp/threshold_before.txt /tmp/threshold_after.txt

Apply the corpus-replay skill pass/fail criteria:

• All prior matches retained + improvement observed: Ship
• All prior matches retained, no change: Reconsider - no measurable effect
• Any prior match lost: Do NOT ship - regression

7. If safe to ship - run full validation

uv run ruff check src/ tests/ uv run pytest

Related

• threshold-corpus-replay skill - detailed replay procedure
• ocr-reviewer agent - review the surrounding code change
• T001 in src/autoscrapper/core/item_actions.py