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

URL: https://docs.hanzo.ai/docs/openapi/o11y/listllmtraces

> Lists LLM traces — gen_ai spans grouped by trace_id, with cost, tokens and latency rolled up across each trace.

`GET /v1/o11y/llm/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/llm/traces` |
| **Method**    | `GET`                                     |
| **Operation** | `ListLLMTraces`                           |
| **Auth**      | `Authorization: Bearer $HANZO_API_KEY`    |

Lists LLM traces — gen\_ai spans grouped by trace\_id, with cost,
tokens and latency rolled up across each trace.

Callers need the viewer role; the runtime's own gate enforces it.

## Request

9 fields.

| Field       | In    | Type    | Required | Description                                                   |
| ----------- | ----- | ------- | -------- | ------------------------------------------------------------- |
| `start`     | query | integer | —        | Start is the start of the window as a unix-millisecond epoch. |
| `end`       | query | integer | —        | End is the end of the window as a unix-millisecond epoch.     |
| `traceId`   | query | string  | —        | TraceID narrows the view to one trace.                        |
| `sessionId` | query | string  | —        | SessionID narrows the view to one conversation.               |
| `userId`    | query | string  | —        | UserID narrows the view to one end user.                      |
| `name`      | query | string  | —        | Name narrows the view to observations of one name.            |
| `model`     | query | string  | —        | Model narrows the view to one model.                          |
| `offset`    | query | integer | —        | Offset is how many rows to skip, for paging.                  |
| `limit`     | query | integer | —        | Limit caps how many rows come back.                           |

## Response

| Status    | Body                  | Meaning           |
| --------- | --------------------- | ----------------- |
| `200`     | o11y.O11yLLMTracesOut | ok                |
| `202`     | Approval              | held for approval |
| `default` | problem-details       | refused           |

`200` body — 15 fields.

| Field                           | In   | Type                   | Always | Description                                            |
| ------------------------------- | ---- | ---------------------- | ------ | ------------------------------------------------------ |
| `data`                          | body | o11y.O11yLLMTracesPage | —      |                                                        |
| `data.items`                    | body | o11y.O11yLLMTrace\[]   | —      | Items are the traces, newest first.                    |
| `data.items[].completionTokens` | body | integer (int64)        | —      | CompletionTokens is the trace's total output tokens.   |
| `data.items[].id`               | body | string                 | —      | ID is the trace id.                                    |
| `data.items[].latencyMs`        | body | number (double)        | —      | LatencyMs is the trace's span, in milliseconds.        |
| `data.items[].observations`     | body | integer (int64)        | —      | Observations is how many observations the trace holds. |
| `data.items[].promptTokens`     | body | integer (int64)        | —      | PromptTokens is the trace's total input tokens.        |
| `data.items[].serviceName`      | body | string                 | —      | ServiceName is the app that emitted it.                |
| `data.items[].sessionId`        | body | string                 | —      | SessionID is the conversation the trace belongs to.    |
| `data.items[].totalCost`        | body | number (double)        | —      | TotalCost is the trace's total cost.                   |
| `data.items[].totalTokens`      | body | integer (int64)        | —      | TotalTokens is the trace's total tokens.               |
| `data.items[].userId`           | body | string                 | —      | UserID is the end user the trace is attributed to.     |
| `data.limit`                    | body | integer (int64)        | —      | Limit is the page cap the read ran with.               |
| `data.offset`                   | body | integer (int64)        | —      | Offset is the row offset this page started at.         |
| `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 llm traces
```

**SDK**

**.ts**

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

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

**.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).list_llm_traces()
```

**.go**

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

resp, _, err := client.O11yAPI.ListLLMTraces(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::list_llm_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).listLLMTraces();
```

**HTTP**

```bash
curl https://api.hanzo.ai/v1/o11y/llm/traces \
  -H "Authorization: Bearer $HANZO_API_KEY"
```

**MCP**

Tool `o11y`, op `ListLLMTraces` — POST the JSON-RPC envelope to `https://api.hanzo.ai/v1/mcp`.

```bash
curl -X POST https://api.hanzo.ai/v1/mcp \
  -H "Authorization: Bearer $HANZO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "jsonrpc": "2.0",
       "id": 1,
       "method": "tools/call",
       "params": {
         "name": "o11y",
         "arguments": {
           "op": "ListLLMTraces",
           "input": {}
         }
       }
     }'
```

---

[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)