Basiq vs Yapily

Basiq

Ten public OpenAPI files, an llms.txt index with Markdown twins and a free self-serve sandbox let an agent start on test data. Live access needs a 12-month plan with an unpublished platform access fee, no SLA or security.txt was found, and the privacy policy says collected content may be kept indefinitely.

Yapily

llms.txt, llms-full.txt, a no-auth docs MCP server and an OpenAPI file. No public pricing; live access starts with a sales form.

Basiq

1. Send the API key verbatim after Basic in the Authorization header of POST /token. Base64-encoding it returns a 400.
2. Send basiq-version: 3.0 on the token request, cache the bearer token for its 60 minutes, and stay under 1,500 token requests per 5 minutes.
3. Send the account holder through the hosted Consent UI in a browser with a CLIENT_ACCESS token bound to their userId. The API alone cannot create a first connection on version 3.0.
4. Poll GET /jobs/{jobId} until verify-credentials, retrieve-accounts and retrieve-transactions all read success before reading accounts or transactions.
5. Follow links.next on GET /users/{userId}/transactions. A page holds at most 500 items, and pending transactions get new ids on each refresh.

Yapily

1. Read llms-full.txt once and cache it; it's the whole documentation in one fetch
2. Add the Modelo sandbox in the Console before your first account-auth-request, or institutions comes back empty
3. Treat a 403 on a data call as a revoked or expired consent and send the user back through authorisation
4. Check the error source field first; USER and INSTITUTION failures won't clear on retry
5. In the UK, call extend-consent with lastConfirmedAt before the reconfirmBy date, or the consent lapses at 90 days