MailMoo
Open MailMoo
DocumentationAPI referenceMCP
EndpointsCampaigns

Edit a sequence message

Rewrites the copy on one step of a campaign's sequence, and the message variants under it. Only the fields you send are changed; the step's send condition, attachments and schedule are left alone. The campaign must be paused. Read the sequence with campaigns.getSequence first to get the step id, and campaigns.getMergeFields for the personalization variables this campaign accepts. A merge field naming anything outside that list is rejected, because it would send to the lead as an empty string rather than failing.

POST/campaigns.updateSequenceMessage

Authorization

bearerAuth
AuthorizationBearer <token>

Enter your MailMoo API key (format: sk_live_...)

In: header

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

curl -X POST "https://example.com/campaigns.updateSequenceMessage" \  -H "Content-Type: application/json" \  -d '{    "campaignId": "13f8bf6d-dc27-4a04-bffe-6e5b13c19ddf",    "stepId": "50e29fb7-490e-4a88-b2f4-2fde4d70423d"  }'
{  "campaignId": "13f8bf6d-dc27-4a04-bffe-6e5b13c19ddf",  "stepId": "50e29fb7-490e-4a88-b2f4-2fde4d70423d",  "type": "SEND_MESSAGE",  "text": "string",  "subject": "string",  "variants": [    {      "id": "string",      "name": "string",      "text": "string",      "subject": "string"    }  ],  "variantAssignment": {    "mode": "default",    "defaultVariantId": "string"  }}

Start or pause a campaign POST

Starts the campaign's sequence, or pauses it. Starting one begins messaging real people, and requires an active subscription and a sequence that passes its readiness checks. Pausing is always allowed.

List a campaign's merge fields GET

The personalization variables this campaign's messages may use, e.g. First Name. Write one as {{First Name | ""}} — the exact display name, plus a fallback. A merge field naming anything outside this list is not an error at send time: it resolves to an empty string, so the lead receives the sentence with a gap in it. campaigns.updateSequenceMessage rejects one rather than letting that happen.