# Create write — POST /v1/metrics/write

URL: https://docs.hanzo.ai/docs/openapi/metrics/post-metrics-write

> Takes `{series:[{name, labels, samples:[{t, v}]}]}`, appends every sample, creating each series on first write, and answers `{written}` — again counting SAMPLES, so three series of ten samples is 30.

`POST /v1/metrics/write`

> [Metrics →](https://docs.hanzo.ai/docs/openapi/metrics) · [All API references →](https://docs.hanzo.ai/docs/openapi) · [Get started →](https://docs.hanzo.ai/docs/guides)

|               |                                         |
| ------------- | --------------------------------------- |
| **Address**   | `https://api.hanzo.ai/v1/metrics/write` |
| **Method**    | `POST`                                  |
| **Operation** | `post_metrics_write`                    |
| **Auth**      | `Authorization: Bearer $HANZO_API_KEY`  |

Takes `{series:[{name, labels, samples:[{t, v}]}]}`, appends every sample, creating each series on first write, and answers `{written}` — again counting SAMPLES, so three series of ten samples is 30.

A series is identified by its name PLUS its whole label set, so adding one label makes a different series rather than annotating an existing one. Timestamps `t` are NANOSECONDS since the Unix epoch; a sample sent without one is stored at 0 and is then excluded by any query that sets a lower bound, which is the usual reason a write that reported success does not read back. Retention is per series and bounded — past 65536 samples the oldest are evicted.

The tenant is the gateway-minted `X-Org-Id` header, falling back to the deployment brand and then `default`. A body that does not decode is 400; nothing else is validated or rejected.

## Request

The document declares no body for `POST /v1/metrics/write`. The handler is typed in cloud but its shape is not yet emitted, so the fields are not listed here — ask MCP's `describe` for `post_metrics_write`, which answers from the running route.

## Response

The document declares no response body for this operation. It answers `200` on success and the platform error shape on failure — see [Errors](https://docs.hanzo.ai/docs/errors).

## Examples

**CLI**

```bash
hanzo metrics write
```

**SDK**

**.ts**

```ts
import { Configuration, MetricsApi } from 'hanzoai';

const api = new MetricsApi(new Configuration({ accessToken: process.env.HANZO_API_KEY }));
const { data } = await api.postMetricsWrite();
```

**.py**

```python
from hanzoai.cloud import ApiClient, Configuration
from hanzoai.cloud.api import MetricsApi

client = ApiClient(Configuration(access_token=os.environ["HANZO_API_KEY"]))
result = MetricsApi(client).post_metrics_write()
```

**.go**

```go
cfg := hanzoai.NewConfiguration()
cfg.AddDefaultHeader("Authorization", "Bearer "+os.Getenv("HANZO_API_KEY"))
client := hanzoai.NewAPIClient(cfg)

resp, _, err := client.MetricsAPI.PostMetricsWrite(context.Background()).Execute()
if err != nil {
	return err
}
```

**.rs**

```rust
use hanzo_client::apis::{configuration::Configuration, metrics_api};

let mut cfg = Configuration::new();
cfg.bearer_access_token = std::env::var("HANZO_API_KEY").ok();

let result = metrics_api::post_metrics_write(&cfg, Default::default()).await?;
```

**.java**

```java
import ai.hanzo.cloud.ApiClient;
import ai.hanzo.cloud.api.MetricsApi;

ApiClient client = new ApiClient();
client.setBearerToken(System.getenv("HANZO_API_KEY"));

var result = new MetricsApi(client).postMetricsWrite();
```

**HTTP**

```bash
curl -X POST https://api.hanzo.ai/v1/metrics/write \
  -H "Authorization: Bearer $HANZO_API_KEY"
```

**MCP**

MCP declares no tool for **metrics** — `tools/list` on `https://api.hanzo.ai/v1/mcp` names the products it does reach. Use HTTP or an SDK.

---

[Metrics API](https://docs.hanzo.ai/docs/openapi/metrics) · [All Hanzo APIs](https://docs.hanzo.ai/docs/openapi) · [Interactive reference](https://docs.hanzo.ai/docs/openapi/reference)