# List an inbox's threads (/docs/api-reference/inboxes/list-inbox-threads)

The inbox's conversations, the one with the latest message first, with a preview of that message. A thread whose `last_inbound_at` equals its `last_message_at` awaits a reply. Pass the last `id` as `after` to get the next page while `has_more` is true.

`GET https://api.coss.com/v1/inboxes/{inbox_id}/threads`

Authenticate with your API key as a bearer token (`Authorization: Bearer coss_test_…`). Responses are JSON with snake_case fields; errors are `{ error: { type, code, message, param?, issues?, request_id } }` (https://coss.com/docs/api-reference/errors.md).

## Path parameters

- `inbox_id` (string, required): The inbox's id.

## Query parameters

- `limit` (integer, 1-100): 1-100, default 20.
- `after` (string, at most 64 characters): Cursor: the `id` of the last item of the previous page.

## Example request

TypeScript (the `coss` package):

```ts
import { Coss } from "coss";

const coss = new Coss({
  apiKey: process.env.COSS_API_KEY,
  baseUrl: "https://api.coss.com",
});

const { data, error } = await coss.inboxes.threads.list("inbox_01k7c8m4q2f3e9v6t5r1n0p8yz");
```

HTTP:

```sh
curl -X GET "https://api.coss.com/v1/inboxes/inbox_01k7c8m4q2f3e9v6t5r1n0p8yz/threads" \
  -H "Authorization: Bearer $COSS_API_KEY"
```

## Response 200

A page of threads.

- `object` ("list", required)
- `data` (object[], required)
  - `object` ("inbox_thread", required)
  - `id` (string, required)
  - `inbox_id` (string, required)
  - `subject` (string | null, required): The first message's subject.
  - `participants` (string[], required): Addresses of everyone in the conversation but the inbox (Bcc'd ones never).
  - `message_count` (integer, required)
  - `preview` (string | null, required): The start of the latest message.
  - `last_message_at` (string, required, date-time)
  - `last_inbound_at` (string | null, required, date-time): When its latest inbound message arrived: later than `last_message_at`'s outbound one means the conversation awaits a reply.
  - `created_at` (string, required, date-time)
- `has_more` (boolean, required)

Example:

```json
{
  "object": "list",
  "data": [
    {
      "object": "inbox_thread",
      "id": "thread_01k7c8m4r0c2b8w9y3d5f6g7h8",
      "inbox_id": "inbox_01k7c8m4q2f3e9v6t5r1n0p8yz",
      "subject": "My order arrived damaged",
      "participants": [
        "jane@example.com"
      ],
      "message_count": 2,
      "preview": "Sorry about that, Jane! A new one is on its way.",
      "last_message_at": "2026-10-10T12:01:00.000Z",
      "last_inbound_at": "2026-10-10T12:00:00.000Z",
      "created_at": "2026-10-10T12:00:00.000Z"
    }
  ],
  "has_more": false
}
```

## Errors

- `400`: The `Coss-Version` header names an unknown API version (`invalid_api_version`).
- `401`: The API key is missing, invalid, revoked or expired (`authentication_error`).
- `403`: The API key lacks the permission this endpoint needs (`permission_error`), or its organization is suspended (`organization_suspended`).
- `404`: No inbox with this id exists in this environment. (`not_found`)
- `422`: A query parameter failed validation (`validation_error`).
- `429`: Too many requests with this API key (`rate_limited`), or too many requests with invalid keys from this address (`too_many_failed_authentications`). Retry after `Retry-After` seconds. Successful responses carry `RateLimit-Limit`, `RateLimit-Remaining` and `RateLimit-Reset` (seconds until the limit is fully restored).
- `500`: Unexpected server error (`api_error` / `internal_error`).
- `503`: The API key could not be verified right now; retry (`service_unavailable`).