> ## Documentation Index
> Fetch the complete documentation index at: https://developers.telnyx.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ports.identity

> `readonly` **identity**: [`AgentHarnessIdentity`](/docs/agent-sdk/harness-sdk/ports/identity#agentharnessidentity)

## On the Agent Runtime

[The runtime adapter](/docs/agent-sdk/harness-sdk/adapters/runtime#on-the-agent-runtime) builds the port from `host`, which carries the protected members of the `Agent` class.

```ts theme={null}
// runtime-adapter.ts
const host = getAgentHarnessHost(agent);
// …
identity: Object.freeze({ id: host.id }),
```

* `id` is [`this.ctx.id`](/docs/agent-sdk/interface/ctx), the id the Agent Runtime assigned to the instance.

## AgentHarnessIdentity

Stable identity asserted by the host, never accepted from a harness input.

**Properties**
**id**

> `readonly` **id**: `string`