OptionalanchorMarker text in the document to anchor this field to (e.g. "Signature:").
OptionalanchorWhen true, don't error if the anchor string isn't found — just skip this field. Defaults to true.
OptionalanchorUnit for the anchor offsets. Defaults to 'pixels'.
OptionalanchorHorizontal offset from the anchor, in anchorUnits.
OptionalanchorVertical offset from the anchor, in anchorUnits.
OptionaldocumentWhich document (1-based index into the envelope's documents) this field targets. Defaults to all documents when omitted (a signature is typically wanted on every document).
Optionalpage1-based page number to place the field on. Drivers adjust for 0-based APIs.
OptionalpageOptionalpageThe target page's true width/height in PDF points (1/72"), when known. A drag-and-drop placer that renders the actual document knows each page's real size, so it should pass these — they let each provider convert the xPercent/yPercent against the ACTUAL page rather than assuming US-Letter. Omit them only when the page size is genuinely unknown, in which case drivers fall back to a US-Letter assumption (correct for Letter docs, off for A4 / legal / landscape). Percentages stay page-size-independent; these just make the back-conversion exact for non-Letter pages.
OptionalrequiredWhether the signer must complete this field. Defaults to true.
OptionaltypeWhat to place. Defaults to 'signature' when omitted.
OptionalxX position as a percentage (0–100) of the page width.
OptionalyY position as a percentage (0–100) of the page height, measured from the top.
Where to place a single field for a signer on the document — the answer to "put the Sign Here box HERE, not at a hardcoded corner."
Two placement strategies, checked in this order:
anchor) — place the field wherever a marker string (e.g."Signature:"or a hidden tag like"\\s1\\") appears in the document text. This is the portable, layout- resilient primitive supported by every provider (DocuSign anchor tabbing, Dropbox Sign / PandaDoc text tags). Preferred whenever the caller controls the document's content.page+xPercent+yPercent) — an absolute fallback for when the document has no usable marker. Coordinates are percentages of the page (0–100), NOT raw pixels, so they're page-size independent; each driver converts to its native unit/origin.If a field supplies neither an anchor nor coordinates, the driver places no tab for it and lets the provider apply its own default. A recipient with an empty/absent
fieldsarray therefore produces no forced placement at all (the provider decides) — which is the correct behavior when the caller hasn't said where signing should happen.