Merge Accounting API vs Rutter Accounting API

Merge Accounting API

12 accounting platforms behind one set of common models, with writes. Launch jumps from free to $650 a month at the fourth linked account.

Rutter Accounting API

Idempotency-Key header on writes, and prefer_sync writes that fall back to async after 30 seconds. Production prices are quote-only.

Merge Accounting API

1. Call GET /invoices/meta/post for the linked account first. Required fields differ by platform
2. Bills and sales invoices are one model. Set type to ACCOUNTS_PAYABLE or ACCOUNTS_RECEIVABLE
3. Append .md to any docs URL for the Markdown twin
4. Check sync_status before reading a freshly linked account. Common models fill in over the first sync
5. Look the record up before retrying a POST that timed out. There's no idempotency key

Rutter Accounting API

1. Send X-Rutter-Version: 2024-08-31 on every call
2. Send an Idempotency-Key on every create so a retry after a timeout doesn't write twice
3. Use response_mode=prefer_sync and handle the 202 async_response anyway
4. Treat 452 as the ledger throttling you and 429 as Rutter's 500-per-10-seconds organisation limit
5. Keep access_token out of logged URLs. The docs only show it as a query parameter