daily-budget-check

1# Daily Budget Check
2 
3A fast daily pulse: are you on pace against today's budget?
4 
5## Input
6 
7The user provides: **$ARGUMENTS**
8 
9This is the **daily budget in dollars** — e.g. `"5"` or `"$5/day"`. If omitted, ask
10for one or derive it from a monthly budget (`monthly / days_in_month`) and state the
11assumption.
12 
13## Data Sources
14 
15| Endpoint | Returns |
16|----------|---------|
17| `GET /api/pricing/cost` | `{ total_cost, breakdown: [{ model, input_tokens, output_tokens, cache_read_tokens, cache_write_tokens, cost, matched_rule }] }` — fleet-wide spend and the avg cost-per-session used to value today's sessions |
18| `GET /api/sessions?limit=200` | Session list with inline `cost` and `started_at` — filter to today (`DATE(started_at) = today`) to isolate today's spend |
19 
20## Method
21 
22Spend has no per-day field, so isolate **today** from the session list:
23 
241. **Today's sessions** = sessions whose `started_at` is today (local date).
252. **Today's spend** = sum of inline `cost` over today's sessions. If inline `cost` is absent for some rows, fall back to `today_session_count × (total_cost / total_session_count)` and flag it as approximate.
263. **Pace**: `fraction_of_day_elapsed = hours_since_midnight / 24`. `expected_by_now = daily_budget × fraction_of_day_elapsed`.
274. **Pace delta** = `today_spend − expected_by_now` (▲ ahead of budget / ▼ behind).
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