# List filter keys

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

> Returns the distinct label keys present in a rule's history entries over the selected range, for building history filters.

`GET /v1/o11y/rules/{id}/history/filter_keys`

> [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/rules/{id}/history/filter_keys` |
| **Method**    | `GET`                                                         |
| **Operation** | `GetRuleHistoryFilterKeys`                                    |
| **Auth**      | `Authorization: Bearer $HANZO_API_KEY`                        |

Returns the distinct label keys present in a rule's
history entries over the selected range, for building history filters. Viewer gate.

## Request

5 fields.

| Field            | In    | Type    | Required | Description                                            |
| ---------------- | ----- | ------- | -------- | ------------------------------------------------------ |
| `id`             | path  | string  | yes      |                                                        |
| `startUnixMilli` | query | integer | —        | StartUnixMilli is the window start, unix milliseconds. |
| `endUnixMilli`   | query | integer | —        | EndUnixMilli is the window end, unix milliseconds.     |
| `searchText`     | query | string  | —        | SearchText narrows the keys to those containing it.    |
| `limit`          | query | integer | —        | Limit caps how many keys come back.                    |

## Response

| Status    | Body                              | Meaning           |
| --------- | --------------------------------- | ----------------- |
| `200`     | o11y.O11yRuleHistoryFilterKeysOut | ok                |
| `202`     | Approval                          | held for approval |
| `default` | problem-details                   | refused           |

`200` body — 11 fields.

| Field                         | In   | Type                      | Always | Description          |
| ----------------------------- | ---- | ------------------------- | ------ | -------------------- |
| `data`                        | body | o11y.GettableFieldKeys    | —      |                      |
| `data.complete`               | body | boolean                   | —      |                      |
| `data.keys`                   | body | object                    | —      |                      |
| `data.keys.*`                 | body | o11y.TelemetryFieldKey\[] | —      |                      |
| `data.keys.*[].description`   | body | string                    | —      |                      |
| `data.keys.*[].fieldContext`  | body | any                       | —      |                      |
| `data.keys.*[].fieldDataType` | body | any                       | —      |                      |
| `data.keys.*[].name`          | body | string                    | yes    |                      |
| `data.keys.*[].signal`        | body | any                       | —      |                      |
| `data.keys.*[].unit`          | body | string                    | —      |                      |
| `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 rules history filter_keys <id>
```

**SDK**

**.ts**

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

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

**.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_rule_history_filter_keys(id='id')
```

**.go**

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

resp, _, err := client.O11yAPI.GetRuleHistoryFilterKeys(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_rule_history_filter_keys(&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).getRuleHistoryFilterKeys();
```

**HTTP**

```bash
curl https://api.hanzo.ai/v1/o11y/rules/<id>/history/filter_keys \
  -H "Authorization: Bearer $HANZO_API_KEY"
```

**MCP**

Tool `o11y`, op `GetRuleHistoryFilterKeys` — 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": "GetRuleHistoryFilterKeys",
           "input": {
             "id": "<id>"
           }
         }
       }
     }'
```

---

[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)