Identify individual sessions with unusually high or low spending using the median and MAD, a measure of spread around it. Filter by time period, adjust detection thresholds, and optionally return a failure exit code for automated checks.
中文简介正在准备中。当前显示英语简介。
MAD-based outlier detection on session spend. Robust to the very outliers it hunts (unlike mean+sigma). Surfaces specific anomalous sessions with modified-z scores; optional --alert-on-outliers exit code for CI gates. Distinct from cost-burn (aggregate trend) — this answers "which INDIVIDUAL session is the outlier?".
安装前可以查看交给 AI 代理的指令内容。
Per-session outlier detection — the diagnostic counterpart to cost-burn's aggregate-trend signal.
| Question | Skill |
|---|---|
| "Is the AGGREGATE rate accelerating?" | cost-burn |
| "Which SPECIFIC sessions are anomalous outliers?" | cost-anomaly ← this |
| "Could we have spent less in aggregate?" | cost-counterfactual |
| "When will we hit budget?" | cost-projection |
Implementation: scripts/anomaly.mjs.
session-* records from cost-tracking namespace.--since window (default: all-time).median(total_cost_usd) and MAD = median(|x - median|).z = 0.6745 * (x - median) / MAD|z| > --threshold (default 3.5).| Approach | What breaks |
|---|---|
mean + sigma | A single $50 session inflates BOTH mean and sigma so badly that subsequent outliers hide inside the new "normal" band. Catastrophic on small samples. |
median + MAD | Both estimators ignore up to 50% of the data — the outliers themselves can't shift them. Robust on n=10. The canonical cutoff |z| > 3.5 is from Iglewicz-Hoaglin (1993). |
| Sessions considered | 5 |
| Threshold (|modified z|) | 3.5 |
| Median spend | $0.100000 |
| MAD | $0.010000 |
| Min / Max | $0.080000 / $5.000000 |
| **Outliers found** | **1** |
## Outlier sessions
| Session | Spend | Deviation | Modified z | Direction |
| outlier- | $5.000000 | +$4.900000 | 330.505 | high |
$ cost anomaly --alert-on-outliers 1
⚠ ALERT: found 1 outlier session(s) (|modified z| > 3.5); threshold was ≥1
exit 1
$ cost anomaly --alert-on-outliers 5
✓ found 1 outlier session(s); under threshold ≥5 — OK
exit 0
# Fail the build if any session this week is a >3.5σ outlier
cost anomaly --since 7d --alert-on-outliers 1 || investigate-bad-session
Most useful when paired with cost-burn:
cost burn --alert-on-acceleration-pct 50 || page-oncall # rate-of-change alert
cost anomaly --alert-on-outliers 1 || investigate # point-anomaly alert
Together they cover "is the average shifting?" AND "is there a single rogue session?" — both can fire independently.
| Direction | Likely cause | Action |
|---|---|---|
high | Long session, stuck in expensive tier, or runaway loop | cost report + cost conversation to investigate |
low | Crash, dropped session, or unfinished work | Verify the session completed normally |
还没有评价。欢迎分享你的使用感受。
无需登录即可发表。欢迎分享使用感受、提问，或说明在哪些环境下无法运行。
还没有评论。来写第一条吧。
Compare models available through the HuggingFace router with chat-ui configuration, research missing models, and write short English descriptions of their architecture and capabilities. Add entries to both production and development configuration files and commit the changes.
中文简介正在准备中。当前显示英语简介。
Create an Architecture Decision Record, a document for recording important design choices, with the next sequential number. It generates a Markdown template, registers the record in AgentDB, and links related decisions found through search.
中文简介正在准备中。当前显示英语简介。
Build a searchable index and relationship graph from ADRs, records of architectural decisions. Import two supported document formats, refresh existing metadata without duplicate relationships, and review summaries of statuses, missing references, and inconsistencies.
中文简介正在准备中。当前显示英语简介。
Rebuild the index of ADRs, records of architectural decisions, after files or relationship lines are deleted. It clears stored records and relationships, indexes the files still present, and checks that the final record count matches.
中文简介正在准备中。当前显示英语简介。
Review code changes against accepted Architecture Decision Records, documents that capture agreed design choices. Report violations, outdated references, compliant changes, and areas without ADR coverage, then suggest code fixes or a new decision record where appropriate.
中文简介正在准备中。当前显示英语简介。
Check saved architecture decision records (ADRs) for broken references, circular replacement relationships, and inconsistent statuses. Use the results to verify imported records or stop a CI check when selected integrity rules fail.
中文简介正在准备中。当前显示英语简介。