For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt, and this page is available as Markdown at /openapi/models/FileSignerData.md.
Array of form set identifiers that this signer is responsible for completing. Each form set contains related fields that the signer must fill out or sign. Multiple signers can be assigned to the same form set, or each signer can have unique form sets.