Developer Documentation

Integrate document signing, forms, cases, and webhooks with NextSign.

Browse the official API reference for authentication, form submission, case lifecycle management, document retrieval, and event-driven integrations.

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Authorization

Find your API key, bearer token flow, and the companyId used in requests.

Forms

Fetch templates, inspect tags, and submit forms to generate new signing cases.

Cases

Create, retrieve, list, and manage signing cases across your integration.

Documents

Retrieve signed files and convert source documents before they are sent.

Webhooks

Subscribe to case and flow events with verified trigger and retry behavior.

Test Environment

Build against a separate test account without affecting production data.