# `zappier/usage`

**Package:** `zappier`  
**Source:** `packages/zappier/src/usage.ts`  
**Lines:** 55

## What this module is

Implementation module in `zappier`. The tables below are extracted from the source (signatures + JSDoc).

## Exports

`UsageEntry`, `UsageSummary`, `summarize`, `UsageRepo`, `InMemoryUsageRepo`

## Types / interfaces / classes

| Kind | Name |
|------|------|
| interface | `UsageEntry` |
| interface | `UsageSummary` |
| interface | `UsageRepo` |
| class | `InMemoryUsageRepo` |

## Functions

| Name | Parameters | Param types (JSDoc) | Returns | Calls (same file / helpers) |
|------|------------|---------------------|---------|-----------------------------|
| `summarize` | `customerId: string, list: UsageEntry[]` | — | `unknown` | see Call graph |

## Methods (class / object)

| Name | Parameters |
|------|------------|
| `record` | `entry: UsageEntry` |
| `listFor` | `customerId: string, since?: Date` |
| `summaryFor` | `customerId: string, since?: Date` |
| `record` | `entry: UsageEntry` |
| `listFor` | `customerId: string, since?: Date` |
| `summaryFor` | `customerId: string, since?: Date` |

## What it imports / requires

_No imports detected._

## Call graph (identifiers invoked)

`summarize`, `reduce`, `record`, `listFor`, `summaryFor`, `push`, `filter`

Each identifier is a call site in this file. Follow the import list to see the defining module; open that module’s MD for parameter and return types.

## Return values (how to read this)

- HTTP route handlers return Express `res.json(...)` bodies (see route docs).
- Zapier `perform` functions return a **single object** (creates) or an **array** (triggers/searches).
- Pricing functions return integer **cents** on `Quote.totalCents`.