Systeme.io MCP Server

Systeme.io

Systeme.io combines email marketing, funnels, courses, and communities. Contacts are central; tags and contact fields segment them.

Data model

• Contacts — leads and customers; carry email, locale, custom fields, and tags.
• Contact fields — custom attribute definitions (slug + label).
• Tags — segmentation labels; assigning tags can trigger automations in your account.
• Communities — membership groups (list-only API surface here).
• Course resources — school courses (list-only API surface here).

Operational order

1. Contact fields — list field slugs before writing custom values on contacts.
2. Tags — list or fetch tag ids before assignment.
3. Contacts — list or fetch one contact for audience work; create/update/delete when mutating.
4. Tag assignment — assign or remove tags on a contact after both ids are known.
5. Communities / courses — read inventory when membership or enrollment context matters.

Write semantics

• Contact create — email required; optional locale and custom field values.
• Contact update — merge-patch by contact id (locale and/or fields only).
• Tag create/rename — POST without id; PUT with tag id.
• Contact field create/rename — POST with fieldName + slug; PATCH by existing slug.
• Tag on contact — assign with contact id + tag id; remove without deleting either row.

Gotchas

• Contact-centric — most workflows start from contacts; list contacts to discover ids.
• limit is mandatory upstream range — Systeme.io rejects limit outside 10–100 (HTTP 422). Default is 25; never pass 5 or 1000.
• Pagination — use startingAfter from the prior page when hasMore is true.
• Communities and courses — no single-resource fetch on the shipped list routes; use collection reads only.
• Contact fields — list-only; there is no single-field GET route upstream.