Add changeset for #235 - thanks @smorimoto (#251)

Author: subtleGradient

.changeset/fix-file-annotation-text-optional.md

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+---
+"@openrouter/ai-sdk-provider": patch
+---
+
+fix: make text field optional in file annotation content schema
+
+When processing PDFs with the file-parser plugin using Mistral OCR, image elements in the response were failing validation. The schema required a `text` field on all content elements, but image elements (`type: "image_url"`) only have `image_url` data—no text. This made it impossible to process PDFs containing images.
+
+Thanks @smorimoto for the fix! (#235)