MailerLite MCP by usefulapi

Upsert subscriber

mailerlite_upsert_subscriber

Destructive

Creates or updates a subscriber (upsert by email). Additive — does NOT send any email. MailerLite API: POST /subscribers.

TableJSON Schema

Name	Required	Description
`email`	Yes	Subscriber email address (upsert key).
`fields`	No	Custom/default field values keyed by field key, e.g. { name, last_name, company }.
`groups`	No	Group id strings to add the subscriber to.
`status`	No	Subscriber status: active \| unsubscribed \| unconfirmed \| bounced \| junk.

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 / fields / additionalProperties / anyOf

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

Score is being calculated.

Add one secure layer between your agents and this server.