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regression-search

Testing & Quality
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Search phone-call history for when a feature regressed (find-regression.py) and drill into a single call to see what went wrong (diagnose-call.py). Skips reading 100+ transcripts by hand.

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Source SKILL.md: https://github.com/sonichi/sutando/blob/HEAD/skills/regression-search/SKILL.md

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Regression Search

Two scripts for hunting down bad calls without reading every transcript:

  1. find-regression.py — search results/calls/calls.jsonl for calls touching a feature, classify each as working/broken, print a sorted timeline.
  2. diagnose-call.py — drill into a single call by SID, report refusals/errors/silences/repeated requests, optionally show metrics from data/call-metrics.jsonl.

Closes #188.

When to use

  • "When did the X feature stop working?" — pass the feature keyword.
  • "Has feature Y improved?" — see the broken/working trend over time.
  • Before shipping a fix — sanity check that the regression is reproducible.

Usage

python3 skills/regression-search/scripts/find-regression.py "record"
python3 skills/regression-search/scripts/find-regression.py "summon" --since 2026-04-01
python3 skills/regression-search/scripts/find-regression.py "play" --json

Flags:

  • --since YYYY-MM-DD — only show calls on/after this date
  • --json — machine-readable output
  • --show-snippet — print a one-line transcript snippet for each call

Heuristics

A call is broken for a query if any of:

  • Sutando refuses ("I can't", "I'm not able", "I'm unable", "sorry I cannot")
  • Sutando reports an error ("error", "failed", "didn't work", "something went wrong")
  • The user repeats the same request 2+ times in a row (Sutando didn't respond usefully)
  • Sutando says "(Silence)" after the user mentions the feature

Otherwise the call is working if Sutando's response includes the feature keyword and isn't flagged broken.

These are intentionally crude — the goal is "good enough to find the regression window without reading 163 transcripts." Tune as you find false positives.

Limitations

  • Keyword matching only. "recording doesn't stop" vs "recording won't start" both match record. The issue calls this out as future work.
  • No semantic understanding. A call where Sutando talks about recording but the user wanted something else still matches.
  • Doesn't correlate with git commits — manual step for now.

diagnose-call.py

python3 skills/regression-search/scripts/diagnose-call.py de1f04733fc2
python3 skills/regression-search/scripts/diagnose-call.py CA701fc4129779... --metrics
python3 skills/regression-search/scripts/diagnose-call.py de1f04733fc2 --json

Accepts a full SID or just the last 12 characters. Reports turn counts, refusals, errors, silences, repeated user requests, and the ending style (normal vs abrupt user end vs sutando silence). With --metrics, also pulls per-event tool-call timeline from data/call-metrics.jsonl (requires PR #223). Exit code 1 if any issues are found, 0 if clean — useful for CI.

Typical workflow: run find-regression.py to surface broken candidates, then diagnose-call.py <sid> to drill into the worst one.

Future work

  • Auto-correlate regression windows with git log
  • Smarter NLP-based query matching (query: "recording doesn't stop" vs "recording won't start")