Use the Velaro REST API with an API key to manage contacts end to end.

Update a contact with custom fields

Send a PATCH to /api/v1/contacts/{id} with core fields and a customFields object of field name and value. Each field must already exist under Contacts > Custom Fields. Values are checked against the field's rules (required, format). If a field name is not defined or a value does not pass, the request returns a 400 that names the field and nothing is changed. A successful response returns the saved contact including customFields.

Read a contact

GET /api/v1/contacts/{id} returns the contact with its tags and custom fields.

Notes

GET /api/v1/contacts/{id}/notes returns a contact's notes, newest first, with page and pageSize. Add a note with POST /api/v1/contacts/{id}/notes.

Tags

Add tags with PATCH or POST on the contact. Remove a tag with DELETE /api/v1/contacts/{id}/tags/{tagId}.

The API key needs the read:contacts permission to read and write:contacts to make changes. The Velaro CLI (velaro contacts tags remove) and the MCP tools contact_update, contact_notes_list and contact_tag_remove offer the same actions.