Getting started

Quickstart

Go from zero to a synced user and a sent email in a few minutes. You'll need an account and an API key.

1. Get an API key

In the Meisa dashboard, open Settings → API Keys and create a key. Give it the scopes you need (for this quickstart: contacts:write and emails:trigger). Copy the key once; it's only shown at creation.

Keys look like meisa_live_…. Send the key in the X-API-Key header on every request. Keep it server-side; never ship it to a browser or mobile client.

2. Verify your key

Confirm the key works and see its scopes:

verify key
curl "https://api.meisa.io/api/v1/ping/" \
  -H "X-API-Key: meisa_live_your_key"

# -> { "status": "ok", "api_key": { "name": "...", "scopes": [...] }, "product": {...} }

3. Sync your first user

Push a user's current state. Use email as the key and your own user ID as external_id. Put product data in custom_fields.

upsert a contact
curl -X POST "https://api.meisa.io/api/v1/contacts/upsert/" \
  -H "X-API-Key: meisa_live_your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "email": "[email protected]",
    "external_id": "usr_12345",
    "first_name": "Sarah",
    "custom_fields": {
      "plan": "free",
      "signup_date": "2026-06-02T10:00:00Z"
    }
  }'

That's the whole sync. If your team has an automation watching for new contacts, it just enrolled this user in your onboarding sequence — no extra code from you.

4. Send a transactional email

First, in the dashboard, create a trigger (template + sender) and give it a trigger_key like verification_code. Then fire it:

trigger an email
curl -X POST "https://api.meisa.io/api/v1/emails/trigger/" \
  -H "X-API-Key: meisa_live_your_key" \
  -H "Content-Type: application/json" \
  -d '{
    "trigger_key": "verification_code",
    "to_email": "[email protected]",
    "variables": { "name": "Sarah", "code": "294817" }
  }'

Where to go next

That's the core loop. Read Contacts & upsert to learn what to put in custom_fields, then How automations work to see how synced data drives tags, sequences, and emails.

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