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

# Create Lookalike Audience

> Create a Meta lookalike audience from an existing source custom audience

Create a Meta lookalike audience from an existing source custom audience. Use meta\_list\_custom\_audiences first to find origin\_audience\_id. The origin audience must have at least 100 people.

|                       |                                  |
| --------------------- | -------------------------------- |
| **App**               | Meta Ads                         |
| **Operation ID**      | `meta_create_lookalike_audience` |
| **Type**              | Action                           |
| **Connection**        | `meta_ads` (required)            |
| **Credits per run**   | 2                                |
| **Agent / MCP tool**  | Yes                              |
| **Requires approval** | Yes (write operation)            |

## Inputs

| Field                       | Type                 | Required | Default | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| --------------------------- | -------------------- | -------- | ------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `account`                   | DynamicAccount       | Yes      | -       | Select Meta Ads account, ask the user for it if not provided.                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| `name`                      | string               | Yes      | -       | Name for the lookalike audience.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| `description`               | string               | No       | -       | Optional audience description.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| `origin_audience_id`        | string or SelectItem | Yes      | -       | Source custom audience ID used as the seed. Use meta\_list\_custom\_audiences to find it. Meta requires the origin audience to have at least 100 people.                                                                                                                                                                                                                                                                                                                                                                |
| `country`                   | string or SelectItem | No       | -       | Two-letter country code for the simple lookalike spec, e.g. US, AE, GB. Required unless lookalike\_spec is provided.                                                                                                                                                                                                                                                                                                                                                                                                    |
| `ratio`                     | number               | No       | `0.01`  | Simple lookalike size as a decimal from 0.01 to 0.20 in 0.01 increments. 0.01 means the top 1% most similar audience in the selected country.                                                                                                                                                                                                                                                                                                                                                                           |
| `starting_ratio`            | number               | No       | -       | Optional start percentage for a lookalike range. Example: starting\_ratio=0.01 and ratio=0.02 creates a 1%-2% lookalike. Must be less than ratio.                                                                                                                                                                                                                                                                                                                                                                       |
| `allow_international_seeds` | boolean              | No       | -       | Optional Meta flag for simple specs. If true, Meta can use seed members from another country when the selected country has fewer than 100 seed members.                                                                                                                                                                                                                                                                                                                                                                 |
| `lookalike_spec`            | object or string     | No       | -       | Advanced Meta lookalike\_spec object as a dict/object or string. Use this only when simple country/ratio fields are not enough. Must include either country or location\_spec, and either ratio or type. Examples: \{'country': 'US', 'ratio': 0.01}; \{'country': 'US', 'starting\_ratio': 0.01, 'ratio': 0.02}; \{'location\_spec': \{'geo\_locations': \{'countries': \['US', 'CA']}}, 'ratio': 0.01}; \{'country': 'US', 'type': 'similarity'}. Do not include origin\_audience\_id, account\_id, name, or subtype. |

### SelectItem

| Field   | Type   | Required | Default | Description                                                                                          |
| ------- | ------ | -------- | ------- | ---------------------------------------------------------------------------------------------------- |
| `value` | string | Yes      | -       | The value of the selectable item.                                                                    |
| `label` | string | Yes      | -       | The label of the selectable item, used for display purposes. If not provided, defaults to the value. |

## Output

**Type**: `Dict`

Returns created lookalike audience id and name.

**Fields**: `audience_id`, `name`