Investigation report
Question: A teammate flagged this metric as behaving strangely over the last period. Investigate it end to end: find every anomalous episode, characterize each one, and support every claim with tool evidence.
Provider: openai-compatible:google/gemini-3.1-flash-lite, 9 turns, 7 tool calls.
The operational metric synthetic-0 was investigated for anomalies. The series shows periodic behavior which was interrupted by three distinct types of anomalies.
Amplitude Anomalies
The robust_zscore detector identified two episodes characterized by amplitude excursions [T3]:
1. 4932-5020: A sharp amplitude excursion (shown in figure_1). This episode has the lowest possible alarm budget, indicating a strong anomaly [T3].
2. 5992-6408: A longer-duration period of amplitude instability (shown in figure_2).
Frequency Anomalies
The cycle_rate detector identified episodes where the pattern's oscillation frequency deviated from the typical periodic behavior [T4]:
1. 0-28: An initial transient at the start of the data.
2. 7085-7129: A period of frequency shift (shown in figure_3). This is the most significant frequency anomaly, with an alarm budget below the resolution of the detector [T4].
3. 7972-7999: A transient frequency shift at the very end of the series.
No episodes of flatline (lack of variance) were detected, confirming the metric remained active throughout the period.
{"findings": [{"start": 4932, "end": 5020, "type": "spike_burst", "summary": "Sharp amplitude excursion.", "evidence": ["T3", "T5"]}, {"start": 5992, "end": 6408, "type": "level_shift", "summary": "Period of amplitude instability.", "evidence": ["T3", "T6"]}, {"start": 7085, "end": 7129, "type": "frequency_shift", "summary": "Significant deviation in the oscillation cycle rate.", "evidence": ["T4", "T7"]}, {"start": 0, "end": 28, "type": "frequency_shift", "summary": "Initial frequency transient.", "evidence": ["T4"]}, {"start": 7972, "end": 7999, "type": "frequency_shift", "summary": "Final frequency transient.", "evidence": ["T4"]}]}
Provenance check
11 numeric claims checked, 0 unsupported (0.0%), 11 weakly supported (100.0%).
| number | verdict | sentence |
|---|---|---|
| 0 | uncited-but-present | The operational metric synthetic-0 was investigated for anomalies. |
| 4932 | uncited-but-present | 4932-5020: |
| 5020 | uncited-but-present | 4932-5020: |
| 5992 | uncited-but-present | 5992-6408: |
| 6408 | uncited-but-present | 5992-6408: |
| 0 | uncited-but-present | 0-28: |
| 28 | uncited-but-present | 0-28: |
| 7085 | uncited-but-present | 7085-7129: |
| 7129 | uncited-but-present | 7085-7129: |
| 7972 | uncited-but-present | 7972-7999: |
| 7999 | uncited-but-present | 7972-7999: |
Verdicts: verified (in the cited tool result), derived (sum or difference of cited values), wrong-citation (exists in another tool result than the one cited), uncited-but-present (no citation given), unsupported (nowhere in the tool log: treat as hallucinated until shown otherwise).
Figures
