# Exposure routes

URL: /code/api/exposure · Id: `page:code/api/exposure`

> Every Exposure Verb as an api.sb route, with its inputs, result, refusals and an example.

Reference for [Exposure](/business/nouns/exposure).

| Noun | System | Run by |
| --- | --- | --- |
| [Exposure](/business/nouns/exposure) | [Experiments](/systems/experiments) | [Analyst](/agents/marketing/analyst) |

### Exposure.create
Creates an Exposure. [Verb page](/business/nouns/exposure/create?interface=api).

```text
POST /{namespace}/exposures
```

Body, as JSON: the inputs. Emits `Exposure.created`.

**Inputs**

| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `unit` | `string` | Yes | What was randomized: a Visitor, a Customer, a request, or an agent choice. |
| `options` | `json` | Yes | Every Variant that was possible at that moment. |
| `propensity` | `number` | Yes | The probability the assigned Variant had, kept for later estimates. |
| `at` | `datetime` | Yes | When the unit met the Variant. |
| `triggered` | `boolean` | No | True when the unit reached the point the Variant changes. |
| `variant` | [Variant](/business/nouns/variant) | No | The Variant the Flag assigned to this unit. |

**Returns**

| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `exposure` | [Exposure](/business/nouns/exposure) | Yes | The Exposure. |

**Refuses when**

| Check | Error | Fix | Then call |
| --- | --- | --- | --- |
| The key is valid, but its scopes do not allow this operation. | [`forbidden`](/code/api/errors/forbidden) | Use a key whose scopes cover the operation, or ask an owner of the namespace to grant them. | None. |

**Example**

```bash
curl -X POST https://api.sb/leaseline.app/exposures \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"unit":"Example unit","options":{},"propensity":1,"at":"2026-10-22T12:00:00Z"}'
```

```json
{
  "api": "https://api.sb/leaseline.app",
  "exposure": {
    "$id": "https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB",
    "$type": "Exposure",
    "unit": "Example unit",
    "options": {},
    "propensity": 1,
    "at": "2026-10-22T12:00:00Z"
  },
  "action": {
    "$id": "https://api.sb/leaseline.app/actions/act_br07HsG8MG",
    "operation": "Exposure.create",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/leaseline.app/actions/act_br07HsG8MG"
  }
}
```

### Exposure.get
Returns one Exposure by id. [Verb page](/business/nouns/exposure/get?interface=api).

```text
GET /{namespace}/exposures/{id}
```

Path: `id`. Query: the other inputs. Reads only: it emits no Event.

**Inputs**

| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `id` | `string` | Yes | The id of the Exposure. |
| `at` | `string` | No | A time or Version name: the record as it stood then. Unset: as it stands now. |

**Returns**

| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `exposure` | [Exposure](/business/nouns/exposure) | Yes | The Exposure. |

**Refuses when**

| Check | Error | Fix | Then call |
| --- | --- | --- | --- |
| The key is valid, but its scopes do not allow this operation. | [`forbidden`](/code/api/errors/forbidden) | Use a key whose scopes cover the operation, or ask an owner of the namespace to grant them. | None. |

**Example**

```bash
curl https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY"
```

```json
{
  "api": "https://api.sb/leaseline.app",
  "$type": "Exposure",
  "$id": "https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB",
  "exposure": {
    "$id": "https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB",
    "$type": "Exposure",
    "unit": "Example unit",
    "options": {},
    "propensity": 1,
    "at": "2026-10-22T12:00:00Z"
  },
  "links": {
    "self": "https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB",
    "up": "https://api.sb/leaseline.app/exposures"
  }
}
```

### Exposure.list
Returns Exposures, newest first, one page at a time. [Verb page](/business/nouns/exposure/list?interface=api).

```text
GET /{namespace}/exposures
```

Query: the inputs. Reads only: it emits no Event.

**Inputs**

| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `limit` | `integer` | No | At most this many records, up to 100. The default is 20. |
| `after` | `string` | No | The cursor from the previous page. |
| `where` | `string` | No | A filter over the properties, such as `paidAt = null and total.amount > 500`. |
| `sort` | `string` | No | Properties to sort by, comma-separated; a leading minus sorts descending. |
| `total` | `boolean` | No | True adds the match count as `meta.total`, exact up to 10,000 matches and estimated above. |
| `facets` | `string` | No | Properties to count by value, comma-separated, returned as `meta.facets`. |
| `fields` | `string` | No | Properties to return on each record, comma-separated; `$id` and `$type` always return. |
| `include` | `string` | No | Related records to embed in place of their URLs, comma-separated. |
| `depth` | `integer` | No | How many levels of related records to embed. The default is 1. |
| `q` | `string` | No | Words to match across the text properties, ranked by relevance. |
| `match` | `string` | No | Ranks the search by `words`, or `meaning`; words is the default. |

**Returns**

| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `exposures` | list of [Exposure](/business/nouns/exposure) | Yes | One page of Exposures. |

**Refuses when**

| Check | Error | Fix | Then call |
| --- | --- | --- | --- |
| The key is valid, but its scopes do not allow this operation. | [`forbidden`](/code/api/errors/forbidden) | Use a key whose scopes cover the operation, or ask an owner of the namespace to grant them. | None. |

**Example**

```bash
curl "https://api.sb/leaseline.app/exposures?limit=20" \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY"
```

```json
{
  "api": "https://api.sb/leaseline.app",
  "$type": "Exposure",
  "exposures": [
    {
      "$id": "https://api.sb/leaseline.app/exposures/exposure_Ua2Xw4KsJB",
      "$type": "Exposure",
      "unit": "Example unit",
      "options": {},
      "propensity": 1,
      "at": "2026-10-22T12:00:00Z"
    }
  ],
  "meta": {
    "limit": 20,
    "after": "exposure_Ua2Xw4KsJB"
  },
  "links": {
    "self": "https://api.sb/leaseline.app/exposures?limit=20",
    "next": "https://api.sb/leaseline.app/exposures?after=exposure_Ua2Xw4KsJB"
  }
}
```