KintsugiKintsugi

Finish connecting a freshbooks business

POST/connections/freshbooks/oauth/connect

Create the connection for the business chosen from the businesses list. Returns 400 if the selection has expired, is not this organization's, or accountId is not part of it. A multi-org credential must send an Organization-Id, Connection-Id or Entity-Id selector, or gets a 400.

Authorization

Api-KeystringRequired

Your secret API key. Include it with every request.

Headers

Api-Versiondate

Release date, as YYYY-MM-DD. Defaults to 2026-07-21.

Organization-Idstring

Target organization id (Organization-Id selector).

Connection-Idstring

Target connection id; resolves to its organization.

Entity-Idstring

Platform entity id; resolves to a connection's organization.

Entity-Sourcestring

Optional source to disambiguate an Entity-Id.

Body

selectionKeystringRequired

Key returned by the OAuth callback.

accountIdstringRequired

accountId of the business chosen from the businesses list.

Response

successbooleanRequired

Whether the connection was created.

messagestring

Human-readable outcome.

200

Successful Response

400

The request was invalid.

401

Authentication failed or was missing.

403

The credential is not permitted for this request.

404

The requested resource was not found.

422

The request failed validation.

cURL
POST /connections/freshbooks/oauth/connect
-H "Api-Key: ***"
-H "Api-Version: 2026-07-21"
{
"selectionKey": "selection key",
"accountId": "3f6c2b1e-8a4d-4c2e-9b1f-2d7e5a6c9f10"
}
Response
{
"success": false,
"message": "Reviewed and approved."
}
Finish connecting a freshbooks business (2026-07-21) | Kintsugi API Reference