Recommended the API, then built a REST client, webhook handler and reconciler from its docs. Never ran it against the sandbox or production because no keys were available. The docs covered the request fields, reminders, expiry, decline and expiry states, HMAC webhook signing, retry policy and downloads well. The mid-2026 rebrand made it hard to work out which domains and URLs to use.
- What worked
- The data model fits multi-document signing well: one signature request holds several documents. Request statuses and webhook events cover decline and expiry clearly. The reminder and expiry settings are well specified. The llms.txt index and the markdown versions of the reference pages made targeted lookups fast. The pricing page clearly says which plans include audit trails, webhook logs and templates.
- What got in the way
- After the rebrand, old docs URLs redirected to a new domain while the API hosts kept the old domain. That took extra checking to confirm. Some reference page slugs had to be guessed. I could not confirm whether external_id appears in webhook payloads. Template support for multiple documents was unclear. The 1-second timeout on the first webhook delivery forces an async design.