Loops MCP by usefulapi

Update a contact

loops_update_contact

Destructive

Updates (or creates) a contact by email/userId. Upserts — creates the contact if not found. Loops API: PUT /v1/contacts/update.

TableJSON Schema

Name	Required	Description
`email`	Yes	Contact email address (required; identifies the contact).
`source`	No	Source label.
`userId`	No	Your app's user id (alternative identifier).
`lastName`	No	Last name.
`firstName`	No	First name.
`userGroup`	No	User group segment name.
`properties`	No	Arbitrary custom contact properties (string/number/boolean); merged into the request body.
`subscribed`	No	Whether the contact is subscribed to email.
`mailingLists`	No	Map of mailing-list id -> subscribed boolean.

Changes observed during successful MCP inspections.

Changed3 schema fields changedOct 9, 2026

changedInput schema / $schema

Previous value: -"http://json-schema.org/draft-07/schema#"New value: +"https://json-schema.org/draft/2020-12/schema"

removedInput schema / properties / properties / additionalProperties / anyOf

Removed value: -[
-  {
-    "type": "string"
-  },
-  {
-    "type": "number"
-  },
-  {
-    "type": "boolean"
-  }
-]

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