REST API

Temporary uploads

Upload files safely with a presigned URL before attaching them to prompt workflows.

Verified against the implementation · 2026-09-09

Three-step upload flow

1
Create the upload
POST /uploads with scope, filename, contentType, and size. PrompTessor returns a temporary presigned upload target.
2
Send the bytes
Upload the exact file bytes and content type to the returned storage URL. Do not send the PrompTessor Authorization header to the storage host.
3
Complete the upload
POST /uploads/{id}/complete so PrompTessor verifies the object. Then pass the returned asset ID in attachmentIds or uploadId.

curl -X POST https://api.promptessor.com/v1/uploads \
  -H "Authorization: Bearer pt_live_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "scope": "analysis",
    "filename": "brief.png",
    "contentType": "image/png",
    "size": 248012
  }'

Upload scopes and retention

Scope	Accepted content types	Maximum size
analysis, refinement, feedback, generation	image/jpeg, image/png, image/webp, image/gif	5 MB
reverse_image	image/jpeg, image/png, image/webp, image/gif	5 MB
reverse_video	video/mp4, video/quicktime, video/webm	100 MB

Valid upload scopes: analysis, refinement, feedback, generation, reverse_image, and reverse_video.
The presigned upload URL expires after 15 minutes.
Temporary assets are retained for 24 hours.
PrompTessor verifies both object metadata and the media file signature before marking an upload ready.
Prompt workflows accept at most five attachment IDs.
Consumed uploads become durable history attachments and cannot be deleted through the temporary-upload endpoint.
Reverse-image processing deletes the asset on a best-effort basis after use.

Plan upload allowances

Pro allows 10 active uploads and 50 MB, Pro+ allows 25 and 250 MB, and Max allows 50 and 1 GB. Pending, uploaded, and processing assets count toward the allowance.

Reverse video currently uses frames

POST /reverse-prompts currently accepts 1–30 data:image/ frame strings plus frameCount and videoDuration. It does not accept a reverse_video upload ID. Do not create a video upload for that endpoint.