Skip to main content
POST
Update a component
At least one of name or lmx must be provided.
When the lmx body changes, the update cascades to every email using this component, and affectedEmailCount reports how many were affected. A change that would introduce a dynamic variable an email using the component cannot use is rejected.

Request

Path parameters

componentId
string
required
The ID of the component.

Body

name
string
The component name.
lmx
string
The component body as an LMX string.

Response

Success

id
string
required
The component ID.
name
string
required
The component name.
lmx
string
required
The component body serialized as LMX.
affectedEmailCount
number
required
The number of emails using this component that were updated by the body change. 0 when only the name changed.

Error

If the request body is invalid, a 400 Bad Request is returned. A 404 Not Found is returned if the component does not exist. If the API key is invalid (or content API is not enabled for your team), a 401 Unauthorized is returned. A 413 Payload Too Large is returned when the LMX body exceeds the size limit. A 422 Unprocessable Entity is returned when the LMX is invalid, or when a body change would break emails using the component. When the update is rejected because a change would push unsupported dynamic variables into an email, the response may include an invalidTags array listing those variables.
message
string
required
An error message describing what went wrong.
invalidTags
string[]
Dynamic variables that the change would push into an email that cannot use them. Present only when the update was rejected for that reason.
Last modified on July 9, 2026