Workspaces
Most of what the API reads and writes lives in a workspace: campaigns, contacts, inboxes, threads. The X-Ken-Workspace-Id header says which one.
The header
Send the workspace id as an integer:
curl "https://api.ken.so/v1/campaigns" \ -H "Authorization: Bearer $KEN_API_KEY" \ -H "Ken-Version: 2026-11-02" \ -H "X-Ken-Workspace-Id: 812"
Each operation in the reference lists X-Ken-Workspace-Id among its parameters when it acts in a workspace. Operations that do not list it ignore it.
When you need it
- Your key reaches exactly one workspace: you can leave the header out, and the request acts in that workspace.
- Your key reaches more than one workspace: a request without the header answers
400with the codeworkspace_required.
Sending it every time is the safe default: the request keeps working when you are added to a second workspace.
Find your workspace ids
List workspaces returns every workspace your key can reach, with its id. Get the current user returns you and your workspaces too.
Resources in other workspaces
A resource in a workspace you are not a member of answers 404 with the code not_found, the same as one that does not exist. The API never confirms that another workspace's resource exists.