---
# @generated by sylphx-gen 0.1.0 from contracts@190f1b33b937c1aef79697684018db853389b521c75e19ff69ac6af609e96f45. Do not edit.
title: "Update an usage meter"
description: "`money.usage_meters.update` (PATCH /v1/{usage_meter.name}): Creates or updates a usage meter."
type: reference
product: payments
summary: "Creates or updates a usage meter."
updated: 2026-09-28
nav: false
---

Creates or updates a usage meter. The unit cannot change once it has recorded usage.

- **Path** `PATCH https://api.sylphx.com/v1/orgs/acme/projects/shop/envs/production/usage_meters/usage-meter`
- **Scope** `billing:write`
- **Effect** `write` — a successful call changes state.
- **Collection** [usage_meters](/docs/api/usage_meters)
- **Query** `update_mask`

## Request

| Field | Type | What it is |
| --- | --- | --- |
| `usage_meter` | `UsageMeter` | The usage meter with its new values; `name` selects it. Required. |
| `update_mask` | `field_mask` | The fields to change. |

### UsageMeter

| Field | Type | What it is |
| --- | --- | --- |
| `name` | `string` | `orgs/{org}/projects/{project}/envs/{env}/usage_meters/{usage_meter}`; the id is the meter key. |
| `meta` | `ResourceMeta` | Resource metadata. |
| `unit` | `string` | The unit of one quantity, for example `token`. It cannot change once the meter has recorded usage. Required. |
| `display_name` | `string` | A name for people. |
| `reservation_optional` | `bool` | Whether usage may be recorded without a reservation. |
| `active` | `bool` | A retired meter (false) refuses new usage; its history stays. |

### ResourceMeta

| Field | Type | What it is |
| --- | --- | --- |
| `labels` | `map<string, string>` | Caller-writable, indexed labels (AIP-122 label rules). |
| `annotations` | `map<string, string>` | Caller-writable, unindexed annotations. |
| `display_name` | `string` | Caller-writable human-readable name. |

## Response

| Field | Type | What it is |
| --- | --- | --- |
| `name` | `string` | `orgs/{org}/projects/{project}/envs/{env}/usage_meters/{usage_meter}`; the id is the meter key. |
| `uid` | `string` | `umtr_<cell><ulid>`; never reused. Output only. |
| `meta` | `ResourceMeta` | Resource metadata. |
| `unit` | `string` | The unit of one quantity, for example `token`. It cannot change once the meter has recorded usage. Required. |
| `display_name` | `string` | A name for people. |
| `reservation_optional` | `bool` | Whether usage may be recorded without a reservation. |
| `active` | `bool` | A retired meter (false) refuses new usage; its history stays. |
| `current_unit_price_nano` | `string` | The unit price in force now, nano-minor, a decimal string; empty before the meter's first price. Output only. |

### ResourceMeta

| Field | Type | What it is |
| --- | --- | --- |
| `generation` | `int64` | Increases by one on every change to `spec`. Output only. |
| `etag` | `string` | Strong ETag (AIP-154): changes on any change to spec, status, or metadata. Send it back as `If-Match` or `etag` to make Update and Delete conditional; a mismatch fails with ABORTED / 409 `ETAG_MISMATCH`. Output only. |
| `create_time` | `timestamp` | When the Resource was created. Output only. |
| `update_time` | `timestamp` | When the Resource last changed. Output only. |
| `delete_time` | `timestamp` | Set while the Resource is being deleted. Output only. |
| `labels` | `map<string, string>` | Caller-writable, indexed labels (AIP-122 label rules). |
| `annotations` | `map<string, string>` | Caller-writable, unindexed annotations. |
| `display_name` | `string` | Caller-writable human-readable name. |
| `creator` | `string` | The principal that created the Resource. Output only. |

## Errors

- [`UNAUTHENTICATED`](/docs/api/errors/UNAUTHENTICATED) — No valid key or token was presented.
- [`PERMISSION_DENIED`](/docs/api/errors/PERMISSION_DENIED) — The key lacks the method's permission.
- [`UNKNOWN_FIELD`](/docs/api/errors/UNKNOWN_FIELD) — The request has a field the schema does not know.
- [`INVALID_FIELD`](/docs/api/errors/INVALID_FIELD) — A field failed validation.
- [`INVALID_STATE`](/docs/api/errors/INVALID_STATE) — The Resource is in a state that forbids the call.
- [`ETAG_MISMATCH`](/docs/api/errors/ETAG_MISMATCH) — The etag sent does not match the Resource's current etag.
- [`IDEMPOTENCY_KEY_REUSED`](/docs/api/errors/IDEMPOTENCY_KEY_REUSED) — An Idempotency-Key was reused with another body.
- [`IDEMPOTENCY_IN_PROGRESS`](/docs/api/errors/IDEMPOTENCY_IN_PROGRESS) — The first call with this Idempotency-Key is still running.

Every error arrives in the body [Errors](/docs/platform/errors) describes.

## Examples

**cURL**

```curl
curl -X PATCH "https://api.sylphx.com/v1/orgs/acme/projects/shop/envs/production/usage_meters/usage-meter" \
  -H "Authorization: Bearer $SYLPHX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name":"orgs/acme/projects/shop/envs/production/usage_meters/usage-meter","unit":"…"}'
```

**TypeScript**

```ts
const response = await sylphx.money.usageMeters.update({ usageMeter: { name: 'orgs/acme/projects/shop/envs/production/usage_meters/usage-meter', unit: '…' } })
```

**Rust**

```rust
let mut req = sylphx::money::UpdateUsageMeterRequest::default();
req.usage_meter = Some(sylphx::money::UsageMeter {
    name: "orgs/acme/projects/shop/envs/production/usage_meters/usage-meter".to_string(),
    unit: "…".to_string(),
    ..Default::default()
});
let response = sx.money().usage_meters().update(req).await?;
```

**CLI**

```bash
sylphx money usage-meters update orgs/acme/projects/shop/envs/production/usage_meters/usage-meter --unit …
```

**MCP**

```json
{ "method_id": "money.usage_meters.update", "args": {"usage_meter":{"name":"orgs/acme/projects/shop/envs/production/usage_meters/usage-meter","unit":"…"}} }
```