# Facts Check API

Webz.io Facts Check uses AI to identify factual claims in online text, then cross-checks them against sources on the web. Each claim is marked `true`, `false`, or `unverified` when no references are found.

Try it in the [Playground](https://app.webz.io/playground).

## Requests

Use either of the following request forms:

| Parameter | Description | Request |
| --- | --- | --- |
| `uuid` | UUID of an existing post. | GET |
| `post_text` | Text to analyze; include the post title and text. | POST |
| `post_link` | Link to the post. | POST |
| `date` | Post publication date. | POST |
| `token` | Your Webz.io token. | GET or POST |

```http
GET https://api.webz.io/fact-check?token=[USER_TOKEN]&uuid=[POST_UUID]
```

```http
POST https://api.webz.io/fact-check?token=[USER_TOKEN]&post_text=[POST_TITLE+POST_TEXT]&post_link=[POST_LINK]&date=[POST_PUBLISHED_DATE]
```

> [!NOTE]
> `post_text` must contain between 100 and 10,000 characters.

## Response

| Field | Description |
| --- | --- |
| `bias` | Detected political bias of the site. |
| `claims[].claim` | Claim extracted from the submitted post. |
| `claims[].verified` | Verification result: `true`, `false`, or `unverified`. |
| `claims[].references` | Sources used to verify the claim. |
| `claims[].references[].text` | Supporting source text. |
| `claims[].references[].link` | Supporting source link. |

```json
{
  "bias": "left",
  "claims": [
    {
      "claim": "Iran's Supreme Leader Ayatollah Ali Khamenei has...",
      "verified": "true",
      "references": [
        {
          "text": "Iran leader Khamenei sees his inner circle hollowed out...",
          "link": "https://www.reuters.com/world/middle-east/"
        }
      ]
    }
  ]
}
```

## Errors and credits

| Status | Meaning |
| --- | --- |
| `204` | No relevant facts were found. |
| `400` | The request is invalid, including an invalid UUID or invalid text input. |
| `401` | The token is missing or incorrect. |
| `402` | There are not enough API calls available. |

Facts Check is a premium feature. Each request consumes five API calls.