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POST
/
audience
/
contacts
/
{contactId}
/
topics
/
{topicId}
Subscribe contact to topic
curl --request POST \
  --url https://app.lettr.com/api/audience/contacts/{contactId}/topics/{topicId} \
  --header 'Authorization: Bearer <token>'
{ "message": "Contact subscribed to topic." }

Documentation Index

Fetch the complete documentation index at: https://docs.lettr.com/llms.txt

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Subscribe a contact to a topic. Returns 201 if the subscription is new, or 200 if the contact was already subscribed. Requires the audience:write scope and is blocked for sandbox API keys.

Authorizations

​
Authorization
string
header
required

API key for authentication

Path Parameters

​
contactId
string<uuid>
required

Contact ID

​
topicId
string<uuid>
required

Topic ID

Response

Contact was already subscribed

​
message
string
required
Example:

"Contact subscribed to topic."