# List traces — GET /v1/o11y/sentinel/traces

URL: https://docs.hanzo.ai/docs/openapi/o11y/get-o11y-sentinel-traces

> Lists the traces a project's captured errors reference, each with how many errors landed on it, when they started and stopped, and the latest message seen — the entry point for "which requests are failing".

`GET /v1/o11y/sentinel/traces`

> [O11y →](https://docs.hanzo.ai/docs/openapi/o11y) · [All API references →](https://docs.hanzo.ai/docs/openapi) · [Get started →](https://docs.hanzo.ai/docs/guides)

|               |                                                |
| ------------- | ---------------------------------------------- |
| **Address**   | `https://api.hanzo.ai/v1/o11y/sentinel/traces` |
| **Method**    | `GET`                                          |
| **Operation** | `get_o11y_sentinel_traces`                     |
| **Auth**      | `Authorization: Bearer $HANZO_API_KEY`         |

Lists the traces a project's captured errors reference, each with how
many errors landed on it, when they started and stopped, and the latest
message seen — the entry point for "which requests are failing".

## Request

3 fields.

| Field     | In    | Type    | Required | Description                                                            |
| --------- | ----- | ------- | -------- | ---------------------------------------------------------------------- |
| `project` | query | string  | yes      | Project is the project to read, as its id.                             |
| `period`  | query | string  | —        | Period is the window to read, relative to now — 1h, 24h, 7d, 14d, 30d. |
| `limit`   | query | integer | —        | Limit caps how many traces come back.                                  |

## Response

| Status    | Body               | Meaning           |
| --------- | ------------------ | ----------------- |
| `200`     | o11y.O11yTracesOut | ok                |
| `202`     | Approval           | held for approval |
| `default` | problem-details    | refused           |

`200` body — 8 fields.

| Field                    | In   | Type               | Always | Description                                            |
| ------------------------ | ---- | ------------------ | ------ | ------------------------------------------------------ |
| `data`                   | body | o11y.O11yTraces    | —      |                                                        |
| `data.items`             | body | o11y.O11yTrace\[]  | —      | Items are the traces, most recent first.               |
| `data.items[].count`     | body | integer (uint64)   | —      | Count is how many captured errors carried it.          |
| `data.items[].firstSeen` | body | string (date-time) | —      | FirstSeen is when the earliest of them was recorded.   |
| `data.items[].lastSeen`  | body | string (date-time) | —      | LastSeen is when the latest was.                       |
| `data.items[].message`   | body | string             | —      | Message is the latest error message seen on the trace. |
| `data.items[].traceId`   | body | string             | —      | TraceID is the trace id.                               |
| `status`                 | body | string             | —      | Status is "success".                                   |

Failure carries the platform error shape — see [Errors](https://docs.hanzo.ai/docs/errors).

## Examples

**CLI**

```bash
hanzo o11y sentinel traces list --project <project>
```

**SDK**

**.ts**

```ts
import { Configuration, O11yApi } from 'hanzoai';

const api = new O11yApi(new Configuration({ accessToken: process.env.HANZO_API_KEY }));
const { data } = await api.getO11ySentinelTraces({ project: 'project' });
```

**.py**

```python
from hanzoai.cloud import ApiClient, Configuration
from hanzoai.cloud.api import O11yApi

client = ApiClient(Configuration(access_token=os.environ["HANZO_API_KEY"]))
result = O11yApi(client).get_o11y_sentinel_traces(project='project')
```

**.go**

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

resp, _, err := client.O11yAPI.GetO11ySentinelTraces(context.Background()).Execute()
if err != nil {
	return err
}
```

**.rs**

```rust
use hanzo_client::apis::{configuration::Configuration, o11y_api};

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

let result = o11y_api::get_o11y_sentinel_traces(&cfg, Default::default()).await?;
```

**.java**

```java
import ai.hanzo.cloud.ApiClient;
import ai.hanzo.cloud.api.O11yApi;

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

var result = new O11yApi(client).getO11ySentinelTraces();
```

**HTTP**

```bash
curl https://api.hanzo.ai/v1/o11y/sentinel/traces?project=%3Cproject%3E \
  -H "Authorization: Bearer $HANZO_API_KEY"
```

**MCP**

MCP reaches **o11y** through the `o11y` tool, which names its 307 operations with its own verbs — this one among them, under a name only MCP declares. `describe` explains any of them:

```bash
curl -X POST https://api.hanzo.ai/v1/mcp \
  -H "Content-Type: application/json" \
  -d '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "tools/call",
       "params": {
         "name": "describe",
         "arguments": {
           "op": "list_o11y_autocomplete_aggregate_attributes"
         }
       }
     }'
```

---

[O11y API](https://docs.hanzo.ai/docs/openapi/o11y) · [All Hanzo APIs](https://docs.hanzo.ai/docs/openapi) · [Interactive reference](https://docs.hanzo.ai/docs/openapi/reference)