Update Contact Topics

Update topic subscriptions for a contact. This page documents the OpenSend-owned API contract for PATCH /contacts/{contactid}/topics.

Raw markdown

PATCH /contacts/{contact_id}/topics

Compatibility note: PATCH /api/contacts/{id}/topics remains available for existing OpenSend integrations; new API clients should prefer the root compatibility path above.

Authentication

Use an OpenSend API key in the Authorization header. Dashboard session cookies are not API credentials for public API clients.

http

Authorization: Bearer os_YOUR_API_KEY

When to use it

Use this route to replace one contact's topic subscription preferences. It only updates topic relationship state; it does not update the contact's name, email, custom properties, or segment memberships.

Parameters

contact_id — contact ID or email for the authenticated tenant.

Request example

json

{
  "topics": [
    { "id": "7a93a5b0-4f2d-4f8e-8e50-9f043c2fd710", "subscription": "opt_in" },
    { "id": "ab9b8b4e-b36d-44a1-8ff0-9971bb9aee4c", "subscription": "opt_out" }
  ]
}

Response

Successful responses confirm the topic relationship update:

json

{
  "object": "contact_topics",
  "contact_id": "520784e2-887d-4c25-b53c-4ad46ad38100",
  "updated": true
}

Errors

OpenSend returns structured errors for missing authentication, validation failures, not-found resources, quota/rate-limit conditions, and unexpected server failures. Treat 404 as either missing or not owned by the caller.

Self-hosting notes

Self-hosted deployments can use the same path on their own OPENSEND_BASE_URL. Run migrations before deploying code that expects new fields, and keep API keys in a secrets manager instead of committing them to source control.