Platform

Platform is the cross-cutting layer for every integration: how you call the API, how requests are secured, what errors look like, and where the OpenAPI spec lives. Use the guides below when you’re wiring your product to Upsign.

Not every action happens only over HTTP. You can create and track documents through the API, then route users into the Upsign web app for advanced document management and sending—see Send documents and Launch workflows. The Getting started guide walks through the end-to-end flow from base URL to webhooks.

For asynchronous lifecycle updates (status changes, completions, and more), subscribe to signed webhooks—start at Webhooks overview.

Core topics

• API reference — interactive OpenAPI (Try it) in the browser
• Authentication — X-Api-Key, partner headers, and mutating requests
• Errors — common HTTP status codes and JSON error shapes
• OpenAPI — bundled openapi.yaml and server-hosted spec