Native signed user images, inline base64, with v3 tool identity/cache behavior.
Official wire reference retrieved 2026-09-10:
https://platform.claude.com/docs/en/build-with-claude/vision
No URL fetch, Files API dependency, resizing, invented MIME, or model probe.
Versions 1/2/3 remain registered and keep refusing images.
Native signed user images, inline base64, with v3 tool identity/cache behavior. Official wire reference retrieved 2026-09-10: https://platform.claude.com/docs/en/build-with-claude/vision No URL fetch, Files API dependency, resizing, invented MIME, or model probe. Versions 1/2/3 remain registered and keep refusing images.