# List callback — GET /v1/provider/slack/link/callback

URL: https://docs.hanzo.ai/docs/openapi/provider/get-provider-slack-link-callback

> The final leg: the user has proved both who they are in Slack and who they are in Hanzo, and this binds the two.

`GET /v1/provider/slack/link/callback`

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

|               |                                                        |
| ------------- | ------------------------------------------------------ |
| **Address**   | `https://api.hanzo.ai/v1/provider/slack/link/callback` |
| **Method**    | `GET`                                                  |
| **Operation** | `get_provider_slack_link_callback`                     |
| **Auth**      | `Authorization: Bearer $HANZO_API_KEY`                 |

The final leg: the user has proved both who they are in Slack and who they are in Hanzo, and this binds the two. It answers a short confirmation page telling them to return to Slack.

The Hanzo credential obtained here is sealed into the connected workspace's own KMS namespace; it is never written to a database column and never logged. A deployment whose secret store is unavailable refuses the link rather than completing it without custody of the credential.

This is one leg of a three-leg flow, and the legs are not interchangeable: a browser is expected to arrive here only from the leg before it. The link URL's state proves the prompt was server-minted and carries the CHAT it started from — it is provenance only, and it never decides which account gets linked. The account identity always comes from the platform's own verified sign-in and a host-bound cookie, so forwarding a link to someone else cannot bind their account, and a session lifted into another browser is refused rather than completed. Each link is single-use, and a deployment without linking configured answers 503.

## Request

`GET /v1/provider/slack/link/callback` takes no parameters and no body — the credential is the whole request.

## 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 provider slack link callback
```

**SDK**

**.ts**

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

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

**.py**

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

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

**.go**

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

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

**.rs**

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

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

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

**.java**

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

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

var result = new ProviderApi(client).getProviderSlackLinkCallback();
```

**HTTP**

```bash
curl https://api.hanzo.ai/v1/provider/slack/link/callback \
  -H "Authorization: Bearer $HANZO_API_KEY"
```

**MCP**

MCP reaches **provider** through the `provider` tool, which names its 38 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_connections"
         }
       }
     }'
```

---

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