Resize a picture
postfjord_resize_mediaMakes new pictures of other shapes from one picture in the media library, one new file per shape (like Magic Resize), and returns their mediaIds. The original never changes. Shapes: 1x1 (square), 4x5 (portrait feed), 9x16 (story and reel), 16x9, 1.91x1, 3x2, 2x3, 4x3; at most one of each in a call. You can call it right after postfjord_upload_media with the new id: it waits a few seconds for the picture to be ready. Each size is a shape alone ("9x16") for the automatic crop, where Postfjord picks the best part, or { aspect, mode, focus, zoom }: mode crop with focus { x, y } (0 to 1 from the top left of the original) on what must stay and zoom 1 to 4, or mode whole to show the whole picture on a soft blurred copy of itself. Use mode whole when a crop would cut off people (heads, hands, feet) or words in the picture (a poster, a menu, a quote). Check the result with postfjord_get_media (previews) before you use it. The new files count toward the plan's storage, and each plan makes a number of resized pictures a day; over it the call is refused. On a retry after a timeout or error, send the same idempotency_key: the first answer comes back and nothing is made or sent twice.
Tool call template
Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {
"mediaId": "<mediaId>",
"sizes": "<sizes>"
},
"name": "postfjord_resize_media"
}
}Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| sizes | Yes | The shapes to make. Common: ["1x1", "4x5", "9x16"]. | |
| mediaId | Yes | The picture to resize, from postfjord_list_media or postfjord_upload_media. | |
| idempotency_key | No | Your own id for this one action, for example post-20261006-launch. Make a new one for each new thing; send the same one again only when you retry. Left out, the exact same call within 10 minutes counts as a retry. |