Docs
PDF info, text, and forms
Use POST /v1/pdf/info for page count and metadata JSON, POST /v1/pdf/text for the existing text layer (no OCR), and rotate / delete-pages / compress for lossless edits. Fill forms on the Forms page.
JSON endpoints: POST /v1/pdf/info, /v1/pdf/text, /v1/pdf/form/fields. Fill with POST /v1/pdf/form/fill. Also rotate, delete-pages, compress, unlock, and from-images.