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

# Caption Hallucination

> Evaluates whether an image caption contains fabricated information not actually visible in the image.

<CodeGroup>
  ```python Python theme={null}
  result = evaluator.evaluate(
      eval_templates="caption_hallucination",
      inputs={
          "image": "https://www.esparklearning.com/app/uploads/2024/04/Albert-Einstein-generated-by-AI-1024x683.webp",
          "caption": "old man"
      },
      model_name="turing_flash"
  )

  print(result.eval_results[0].output)
  print(result.eval_results[0].reason)
  ```

  ```typescript JS/TS theme={null}
  import { Evaluator, Templates } from "@future-agi/ai-evaluation";

  const evaluator = new Evaluator();

  const result = await evaluator.evaluate(
    "caption_hallucination",
    {
      image: "https://www.esparklearning.com/app/uploads/2024/04/Albert-Einstein-generated-by-AI-1024x683.webp",
      caption: "old man"
    },
    {
      modelName: "turing_flash",
    }
  );

  console.log(result);
  ```
</CodeGroup>

| **Input** |                    |          |                                               |
| --------- | ------------------ | -------- | --------------------------------------------- |
|           | **Required Input** | **Type** | **Description**                               |
|           | `image`            | `string` | URL or file path to the image being captioned |
|           | `caption`          | `string` | The caption text to evaluate                  |

| **Output** |            |                                                                                                                                                                                              |
| ---------- | ---------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|            | **Field**  | **Description**                                                                                                                                                                              |
|            | **Result** | Returns Passed or Failed, where Passed indicates the caption accurately represents what's in the image without hallucination and Failed indicates the caption contains hallucinated elements |
|            | **Reason** | Provides a detailed explanation of the evaluation                                                                                                                                            |

***

### What to do If you get Undesired Results

If the caption is evaluated as containing hallucinations (Failed) and you want to improve it:

* Stick strictly to describing what is visibly present in the image
* Avoid making assumptions about:
  * People's identities (unless clearly labeled or universally recognizable)
  * The location or setting (unless clearly identifiable)
  * Time periods or dates
  * Actions occurring before or after the captured moment
  * Emotions or thoughts of subjects
  * Objects that are partially obscured or ambiguous
* Use qualifying language (like "appears to be," "what looks like") when uncertain
* Focus on concrete visual elements rather than interpretations
* For generic descriptions, stay high-level and avoid specifics that aren't clearly visible

***

### Comparing Caption Hallucination with Similar Evals

* [**Is AI Generated Image**](https://docs.futureagi.com/future-agi/get-started/evaluation/builtin-evals/is-AI-generated-image): Caption Hallucination evaluates the accuracy of image descriptions, while Is AI Generated Image determines if the image itself was created by AI.
* [**Detect Hallucination**](https://docs.futureagi.com/future-agi/get-started/evaluation/eval-definition/detect-hallucination): Caption Hallucination specifically evaluates image descriptions, whereas Detect Hallucination evaluates factual fabrication in text content more broadly.
* [**Factual Accuracy**](https://docs.futureagi.com/future-agi/get-started/evaluation/eval-definition/factual-accuracy): Caption Hallucination focuses on whether descriptions match what's visible in images, while Factual Accuracy evaluates correctness of factual statements more generally.