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

# twitter.media.alt_text_max_graphemes

> Alt text on a tweet's media is capped at 1000 graphemes.

## What it checks

For every media item that carries `altText`: `countGraphemes(altText) <= 1000`.

Counted with `Intl.Segmenter`, so a compound emoji (`👨‍👩‍👧‍👦`) is one grapheme — same counter the platform uses.

## Why

X's v1.1 metadata endpoint (`/1.1/media/metadata/create`) caps alt text at 1000 characters. Beyond that the metadata write fails — and because alt-text writes are best-effort by design (they live on a separate deprecation track from `/2/tweets`), a silent failure means the tweet posts without accessibility metadata you intended to attach. Preflight makes that explicit.

## Failure response

```json theme={"system"}
{
  "error": {
    "code": "preflight_failed",
    "rule": "twitter.media.alt_text_max_graphemes",
    "platform": "twitter",
    "message": "Alt text is 1432 graphemes; X allows at most 1000.",
    "remediation": "Shorten alt text to 1000 graphemes or fewer."
  }
}
```

## Remediation

Trim the alt text. If you need more context, put it in the tweet body — alt text is for screen readers, the body is for everyone.

## Related

* [`twitter.text.max_graphemes`](/preflight/twitter-text-max_graphemes)