Apideck Accounting API + MCP vs FreshBooks API

Apideck Accounting API + MCP

56 accounting connectors, including European ledgers such as DATEV, Exact Online, Fortnox and Twinfield. No published rate limits of Apideck's own, only connector limits mirrored in headers.

FreshBooks API

OAuth scopes split read and write per resource, such as user:invoices:read. Rate limits have no numbers, status code or headers.

Apideck Accounting API + MCP

1. Stay in dynamic mode and search for tools. Static mode loads all 362 schemas
2. Start the MCP with --lock-identity (or ?lock_identity=true) when one agent serves one customer
3. Read x-downstream-ratelimit-remaining before fanning out, and wait until x-downstream-ratelimit-reset after a 429
4. List before you retry a create that timed out. Writes aren't idempotent and there's no idempotency key
5. Pass fields= on list calls to cut the response to the columns you need

FreshBooks API

1. Call /auth/api/v1/users/me first and keep both ids. Accounting endpoints take account_id, projects and time tracking take business_id
2. Serialise token refreshes. Issuing a new refresh token kills the old one at once
3. Mark an invoice as sent (action_mark_as_sent) or email it. Reports ignore drafts
4. Send x-api-version: 2023-09-25 on journal entry calls
5. Back off on any throttling response yourself. There's no Retry-After to read and no published limit