Register as a Greenhouse partner and obtain OAuth 2.0 client credentials; Harvest v3 uses Bearer tokens obtained via the OAuth 2.0 client credentials or authorization code flow depending on your integration type.
Request the appropriate Harvest v3 scopes for your integration — for example, harvest:applications:list to read applications and harvest:candidates:read to access candidate data.
Configure webhook subscriptions in Greenhouse under the Events tab and enable the Assessments Order and Background Check Order event types for the relevant jobs.
When Greenhouse fires the assessment order webhook, parse the payload to extract the candidate ID, application ID, job stage, and the partner test ID that was ordered.
Use the Harvest v3 API to fetch the full candidate and application context if needed, then dispatch the assessment invitation on the third-party platform.
When the assessment completes, POST the result back to Greenhouse using the assessment result endpoint associated with the partner integration.
Known gotchas
Harvest v1 and v2 APIs are deprecated and will be removed on August 31, 2026 — any existing integrations using those versions must be migrated to v3 before that date.
Greenhouse webhook payloads do not include full candidate details — you must make a follow-up Harvest API call to fetch candidate and application data using the IDs in the webhook body.
OAuth token expiry is not always signaled in advance; implement token refresh logic and handle 401 responses gracefully to avoid dropped webhook processing.
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp