/slo-check

name: slo-check
description: >
  Define and check simple service-level objectives for Claude Code from Agent
  Monitor data — session completion rate, tool success rate
  (PostToolUse/PreToolUse), and error rate (APIError/total) — then compare each
  to its target and report the error budget remaining. Use when reporting
  reliability or when someone asks "are we meeting our SLOs?".

SLO Check

Turn raw event counts into a clear SLO scorecard with error-budget accounting.

Input

The user provides: **$ARGUMENTS**

This may be:

• empty — use the default SLO targets below over all available data
• targets like "completion=95 success=99 error=1" — override the defaults (percentages)
• a window like "last 7d" or "today" — restrict the measurement period

Default SLO targets: completion rate ≥ 95%, tool success rate ≥ 99%, error rate ≤ 1%.

Data Sources

| Endpoint | Returns | |----------|---------| | `GET /api/analytics` | `event_types` (PreToolUse, PostToolUse, APIError counts), `sessions_by_status`, `daily_events` (365d), `daily_sessions` (365d) — the raw numerators/denominators for every SLI | | `GET /api/stats` | `total_sessions`, `total_events`, `events_today`, `sessions_by_status` — fleet totals and recency | | `GET /api/events?session_id=X` | Per-session stream — drill into the sessions that breach an SLO |

Report Sections

1. Service Level Indicators (SLIs)

Compute each SLI from `GET /api/analytics` / `GET /api/stats`:

• **Completion rate** = completed sessions / total sessions (from `sessions_by_status`; count `active`/`running` as in-flight, exclude them from the denominator if still open).
• **Tool success rate** = `PostToolUse / PreToolUse` (capped at 100%).
• **Error rate** = `APIError / total_events`.

Within a window, derive the numerators/denominators from `daily_events` / `daily_sessions`.

2. SLO Scorecard

For each SLI, compare to its target and mark MET ✅ or BREACHED ❌.

3. Error Budget

For each objective, report the **error budget** and how much remains:

• Budget = `1 − target` (e.g., 1% for a 99% target).
• For "higher-is-better" SLOs (completion, success): remaining = `(observed − target) / (1 − target)`.
• For "lower-is-better" SLOs (error rate): remaining = `(target − observed) / target`.
• A negative result means the budget is exhausted — report how far over (e.g., "2.7× over budget").

4. Breach Drill-Down

For any breached SLO, list the sessions contributing most to the breach (most failed tools or most APIErrors) via `GET /api/events?session_id=X`.

Output

• A Markdown scorecard table: SLI | observed | target | status | error budget remaining.
• Rates as percentages to 2 decimals; any currency in USD to 4 decimals.
• Cite exact counts and `session_id` values — never fabricate numerators or denominators.
• End with the SLO most at risk and the single action that would recover the most budget.
• Read-only: only report what the API returns. If `curl` cannot reach `http://localhost:4820`, tell the user to start the dashboard with `npm start` from the repo root.