> ## 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.

# media.bytes_inline_unsupported

> Inline base64 isn't accepted on this platform's URL-only ingest path. Upload via POST /v1/media first.

## What it checks

The platform's publish path requires a URL — Meta's create-container flow, Pinterest's pin creation — and the request supplied `bytesBase64` instead.

We could buffer + upload to a temp URL on the fly, but that path has had enough surprise failures (timeouts, signed URL expiry) that we make the caller do it explicitly.

## Remediation

Upload via [`POST /v1/media`](/guides/upload-media) and use the returned `mediaId`. Inline bytes work fine for Bluesky and Twitter; the URL-only platforms route through media first.