Plaid vs Yapily

Plaid

Public OpenAPI file, llms.txt with about 250 entries and a Markdown twin of every docs page. No prices before a Production application, and Transactions, Liabilities and Investments bill per Item each month until removed.

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.

Plaid

1. Point calls at https://sandbox.plaid.com until you hold a Production secret; request shapes are the same
2. Create a sandbox Item with /sandbox/public_token/create and ins_109508, then /item/public_token/exchange, no Link UI needed
3. Use /transactions/sync with its cursor and back off on 429 RATE_LIMIT_EXCEEDED yourself, since no Retry-After comes back
4. Call /item/remove when the user is done, or subscription products keep billing
5. Send an idempotency_key on /transfer/authorization/create so a retried request can't authorise twice

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