OpenSend docs
Retrieve Contact Topics
Get topic subscriptions for a contact. This page documents the OpenSend-owned API contract for GET /contacts/{contactid}/topics.
GET /contacts/{contact_id}/topics
Compatibility note: GET /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.
Authorization: Bearer os_YOUR_API_KEYWhen to use it
Use this route to inspect one contact's topic preference state. It returns topic subscription rows for the target contact and does not modify contact fields.
Parameters
contact_id— contact ID or email for the authenticated tenant.
Response
Successful responses return topic preferences for the contact:
{
"object": "list",
"data": [
{
"id": "7a93a5b0-4f2d-4f8e-8e50-9f043c2fd710",
"name": "Product Updates",
"subscription": "opt_in"
}
]
}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.