Circularo signs, manages and archives documents. Its API lets you build that into your own product: upload a file, turn it into a document, send it to the people who have to sign or approve it, and collect the signed result together with the evidence of who did what and when. Everything is server-to-server and authenticated with a single API key.
These pages show how to use the API through integrator scenarios. Each one takes a single job an integration has to do, works through it call by call, and shows the real requests and responses of a run that actually happened. The API reference documents every endpoint, parameter and error code; the scenarios tell you which of them you need, in what order, and what to watch out for.
How the documentation is arranged
Six chapters, arranged the way a working integration usually grows. Getting Started gets you a key and a signed document. Signing & Approvals then takes the sending side as far as it goes — several recipients and routing, fields placed on the page, links you deliver yourself, identity verification, templates, signing alone. Documents & Files covers everything the signing revolves around: content in and out, metadata, search, annotations and seals, folders, evidence and bulk exports. Robust Integrations is what a happy path is missing before it goes live — errors, safe retries, paging, concurrent writes and webhooks. The last two are for the narrower audiences: Administration for the accounts, groups and the organization-wide log of what everyone did, Reporting for the state of the work as rows or as figures.
Chapters use what earlier chapters taught and nothing more, so reading in order always works. Each page is also self-contained enough to be read on its own when a job brings you to it.
Where to start
Begin with Getting Started. It explains the handful of concepts the rest of the documentation assumes, gets you an API key, and sends a document for signature over three endpoints — about fifteen minutes from nothing to a signed PDF.
After that, read the chapter that covers the job in front of you. Whatever that job is, Robust Integrations is worth reading before the integration carries real volume and real documents.