Resolve "yesterday" to a concrete ISO date range relative to your run time —
yesterday. Returns inclusive civil dates plus exact UTC instants so you have
temporal context without computing dates by hand. Read-only: no writes, no
network. Use before a task scoped to yesterday (daily reports, "what changed yesterday").
Installs into .claude/skills of the current project.
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---
name: yesterday
description: |
Resolve "yesterday" to a concrete ISO date range relative to your run time —
yesterday. Returns inclusive civil dates plus exact UTC instants so you have
temporal context without computing dates by hand. Read-only: no writes, no
network. Use before a task scoped to yesterday (daily reports, "what changed yesterday").
allowed-tools:
- Bash
---
## /yesterday
Get the concrete date range for **yesterday** by running the bundled resolver:
```bash
node "$AGENT_DIR/.claude/skills/temporal/when.mjs" yesterday
```
It prints a human-readable line plus a JSON record:
- `start` / `end` — inclusive civil dates (`YYYY-MM-DD`) in your local timezone
- `startUtc` / `endExclusiveUtc` — the same window as a half-open `[start, end)`
range of exact UTC instants, for timestamp-based queries
- `days`, `timezone`, `asOf` — the span, your timezone, and when this resolved
Use the returned dates as the time bounds for the task at hand. **Do not derive
dates by hand** — this resolver is the source of truth. For the full window list
or an arbitrary range (e.g. `last45days`, `last6months`), see the `/temporal` skill.
