# Create flag

URL: https://docs.hanzo.ai/docs/openapi/flag/post-flag

> Runs the caller's flag definitions for one identity and returns the flag verdict: which flags are on (or which variant), their payloads, and whether any definition failed to compute.

`POST /v1/flag`

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

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

Runs the caller's flag definitions for one identity and returns the
flag verdict: which flags are on (or which variant), their payloads,
and whether any definition failed to compute. Evaluation is in-process over the
caller's own (org, project) definitions — no network hop, no shared KV — so a
tenant can only ever evaluate its own flags.

## Request

3 fields, body `application/json` (required).

| Field               | In   | Type   | Required | Description                                                                |
| ------------------- | ---- | ------ | -------- | -------------------------------------------------------------------------- |
| `distinct_id`       | body | string | —        | DistinctID is the identity the flags are evaluated for.                    |
| `groups`            | body | any    | —        | Groups are the group-level properties, keyed by group type index.          |
| `person_properties` | body | any    | —        | PersonProperties are the person-level properties conditions match against. |

## Response

| Status    | Body            | Meaning |
| --------- | --------------- | ------- |
| `200`     |                 | ok      |
| `default` | problem-details | refused |

`200` body — 1 field.

| Field    | In   | Type | Always | Description |
| -------- | ---- | ---- | ------ | ----------- |
| `(body)` | body | any  | yes    |             |

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

## Examples

**CLI**

```bash
hanzo flag create
```

**SDK**

**.ts**

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

const api = new FlagApi(new Configuration({ accessToken: process.env.HANZO_API_KEY }));
const { data } = await api.postFlag({ distinct_id: "<distinct_id>", groups: "<groups>" });
```

**.py**

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

client = ApiClient(Configuration(access_token=os.environ["HANZO_API_KEY"]))
result = FlagApi(client).post_flag(distinct_id="<distinct_id>", groups="<groups>")
```

**.go**

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

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

**.rs**

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

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

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

**.java**

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

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

var result = new FlagApi(client).postFlag();
```

**HTTP**

```bash
curl -X POST https://api.hanzo.ai/v1/flag \
  -H "Authorization: Bearer $HANZO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "distinct_id": "<distinct_id>",
       "groups": "<groups>"
     }'
```

**MCP**

MCP reaches **flag** through the `flag` tool, which names its 8 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": "get_flag_activity"
         }
       }
     }'
```

---

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