Hellosign

The API covers signature requests, embedded signing, templates, unclaimed drafts, accounts, and webhooks. Agents can create signature requests with specific signers and documents, embed the signing experience in the application UI, template-based requests for standardized documents, and retrieve signed PDFs with audit trails. The event callback system delivers real-time signing status updates without polling.

Reliability is production-grade for an established e-signature platform. Dropbox Sign handles the signing infrastructure, notification delivery to signers, and document storage. Teams implementing signature automation should use the webhook callback system for signing status updates rather than polling, as signature completion can take hours or days depending on signer availability.

Dropbox Sign (formerly HelloSign) is an electronic signature platform with a REST API for creating signature requests, tracking signing status, managing templates, and retrieving completed documents. Its Embedded Signing API enables in-app signing experiences without redirecting users to a Dropbox Sign-hosted page. For agents automating document signature workflows — contract execution, onboarding agreements, approval flows — the REST API provides the full lifecycle from request creation to completed document retrieval.

Authentication uses API keys for the REST API — both basic key authentication and OAuth 2.0 for multi-tenant integrations where customers use their own Dropbox Sign accounts. The API key model is straightforward for backend agents making signature requests on behalf of the application.

Documentation is thorough and covers the signature request, embedded signing, and template APIs clearly with code examples. The embedded signing documentation is particularly detailed for teams building in-app signing flows. Teams evaluating Dropbox Sign versus DocuSign for e-signature API integration should compare the pricing model, embedded signing UX quality, and template management capabilities.