# Search availability across hosts (/docs/api-reference/scheduling-availability/search-scheduling-availability)

For "who's free" pages: each matching host's soonest slots, soonest first, across up to 500 hosts.

`POST https://api.coss.com/v1/scheduling/availability/search`

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).

## Request body

- `event_type` (string, required): The event type's id or uid.
- `start` (string, required): An ISO 8601 instant with an offset.
- `end` (string, required): An ISO 8601 instant with an offset.
- `attributes` (map of string | string[]): Only hosts matching all of these.
- `hosts` (string[], at most 500 items)
- `slots_per_host` (integer, 1-50, default 3)
- `limit` (integer, 1-500, default 50): Hosts to return, soonest availability first.

## 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.scheduling.availability.search({
  event_type: "evtype_01kd2m9a0b1c2d3e4f5g6h7j8m",
  start: "2027-01-04T00:00:00.000Z",
  end: "2027-01-18T00:00:00.000Z",
  attributes: {
    licensed_in: "CA",
  },
});
```

HTTP:

```sh
curl -X POST "https://api.coss.com/v1/scheduling/availability/search" \
  -H "Authorization: Bearer $COSS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "event_type": "evtype_01kd2m9a0b1c2d3e4f5g6h7j8m",
  "start": "2027-01-04T00:00:00.000Z",
  "end": "2027-01-18T00:00:00.000Z",
  "attributes": {
    "licensed_in": "CA"
  }
}'
```

## Response 200

Hosts with slots.

- `object` ("list", required)
- `data` (object[], required)
  - `host` (string, required)
  - `uid` (string | null, required)
  - `slots` (object[], required)
    - `start` (string, required)
    - `end` (string, required)
- `has_more` (boolean, required)

Example:

```json
{
  "object": "list",
  "data": [
    {
      "host": "host_01kd2m9a0b1c2d3e4f5g6h7j8m",
      "uid": "doctor_482",
      "slots": [
        {
          "start": "2027-01-04T15:00:00.000Z",
          "end": "2027-01-04T15:30:00.000Z"
        }
      ]
    }
  ],
  "has_more": false
}
```

## Errors

- `400`: The body is not valid JSON (`invalid_json`). Also when 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`: Nothing with this id or uid exists in the environment (`not_found`).
- `415`: The body is not sent as `application/json` (`unsupported_media_type`).
- `422`: The request failed validation (`validation_error`, see `issues`), or can't be done: see `code`.
- `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`).