openapi: 3.2.0 info: version: 1.0.0 title: Customer.io App Info API description: 'Our App API provides ways to trigger messages and retrieve information about people, campaigns, broadcasts, and more. # Overview The App API provides methods to send newsletters, transactional messages, and API-triggered broadcasts. You can create newsletters from scratch and update transactional messages and API-triggered broadcasts. For transactional messages and API-triggered broadcasts, your payload acts as a message "trigger" and can contain `data` that you reference in your messages using liquid—`{{trigger.}}`. The other endpoints help you retrieve information about people, segments, campaigns, broadcasts, etc; it also lets you update campaign actions, messages, newsletter variants, etc. Aside from the [API-triggered broadcast](#triggerBroadcast) (1 per 10 seconds) and [Transactional](#sendEmail) (100 per second) endpoints, requests are limited to 10 per second. # Use our Postman collection We''ve generated a Postman collection to help you get started with our APIs. If you fork this collection, you might want to disable the *Watch original collection* option. We automatically update our Postman collection whenever we release changes to our documentation, even if we don''t change our APIs—which happens daily! Rather than being flooded with Postman notifications, you can check out our [Release Notes](/release-notes/) for updates to our APIs. **NOTE**: Postman endpoints default to our US APIs. If you''re in our European (EU) region, you''ll need to add `-eu` to the server variables (`track_api_url` and `app_api_url`). [Run In Postman](https://god.gw.postman.com/run-collection/23697545-2931c004-e63d-4cdc-bf4b-e685ba6da42d?action=collection%2Ffork&source=rip_markdown&collection-url=entityId%3D23697545-2931c004-e63d-4cdc-bf4b-e685ba6da42d%26entityType%3Dcollection%26workspaceId%3Db886877f-fc09-475f-84fe-6221a98f4d18#?env%5BCustomer.io%20API%20Environment%5D=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) # Server addresses: US and EU Customer.io hosts services in the United States (US) and European Union. Select the appropriate server address for your region. | Region | Server Address | | :-- | :-- | | US | https://api.customer.io | | EU | https://api-eu.customer.io | # Authentication All requests to the Customer.io App API use an [App API Key](#App-API-Key). To authenticate, provide your key as a Bearer token in a HTTP Authorization header. You can create and manage your API keys—including keys with different scopes—in [your account settings page](https://fly.customer.io/settings/api_credentials?keyType=app). Each operation on this page references the authorization header it requires. # Rate Limits Most endpoints on this page are limited to 10 requests per second. The exceptions are: * The [transactional email](#operation/sendEmail) endpoint is limited to 100 requests per second. * The [API-triggered broadcast endpoint](#operation/triggerBroadcast) is limited to 1 request every 10 seconds. **Rate limits are subject to change. We may adjust these thresholds to ensure stable performance for all customers.** ' servers: - url: https://api.customer.io description: The base URL for broadcasts, transactional messages, and data-retrieval APIs. These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app). - url: https://api-eu.customer.io description: The base URL for broadcasts, transactional messages, and data-retrieval APIs (EU region). These endpoints use bearer authorization, and require a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app). tags: - name: Info description: 'Returns the list of addresses used by Customer.io. You must add add these addresses to your allowlist when using a custom SMTP provider and blocking unknown IP addresses. ' paths: /v1/info/ip_addresses: servers: - url: https://api.customer.io description: This API uses bearer authorization, requiring a [token that you generate in the UI](https://fly.customer.io/settings/api_credentials?keyType=app). get: summary: List IP addresses operationId: getCioAllowlist security: [] description: 'Returns a list of IP addresses that you need to allowlist if you''re using a firewall or [Custom SMTP](/journeys/channels/email/deliverability/custom-smtp/use-your-smtp-server) provider''s IP access management settings to deny access to unknown IP addresses. These addresses apply to all message types and webhooks, except push notifications. ' tags: - Info responses: '200': description: Returns an array of IP addresses. content: application/json: schema: type: object properties: ip_addresses: type: array items: type: string format: ip address example: - 35.188.196.183 - 104.198.177.219 - 104.154.232.87 - 130.211.229.195 - 104.198.221.24 - 104.197.27.15 - 35.194.9.154 - 104.154.144.51 - 104.197.210.12 - 35.225.6.73 '429': description: Your request is over the 10-per-second limit. x-codeSamples: - lang: Shell + Curl source: "curl --request GET \\\n --url https://api.customer.io/v1/info/ip_addresses" - lang: Node + Native source: "const http = require(\"https\");\n\nconst options = {\n \"method\": \"GET\",\n \"hostname\": \"api.customer.io\",\n \"port\": null,\n \"path\": \"/v1/info/ip_addresses\",\n \"headers\": {}\n};\n\nconst req = http.request(options, function (res) {\n const chunks = [];\n\n res.on(\"data\", function (chunk) {\n chunks.push(chunk);\n });\n\n res.on(\"end\", function () {\n const body = Buffer.concat(chunks);\n console.log(body.toString());\n });\n});\n\nreq.end();" - lang: Ruby + Native source: 'require ''uri'' require ''net/http'' require ''openssl'' url = URI("https://api.customer.io/v1/info/ip_addresses") http = Net::HTTP.new(url.host, url.port) http.use_ssl = true http.verify_mode = OpenSSL::SSL::VERIFY_NONE request = Net::HTTP::Get.new(url) response = http.request(request) puts response.read_body' - lang: Python + Python3 source: 'import http.client conn = http.client.HTTPSConnection("api.customer.io") conn.request("GET", "/v1/info/ip_addresses") res = conn.getresponse() data = res.read() print(data.decode("utf-8"))' - lang: Go + Native source: "package main\n\nimport (\n\t\"fmt\"\n\t\"net/http\"\n\t\"io/ioutil\"\n)\n\nfunc main() {\n\n\turl := \"https://api.customer.io/v1/info/ip_addresses\"\n\n\treq, _ := http.NewRequest(\"GET\", url, nil)\n\n\tres, _ := http.DefaultClient.Do(req)\n\n\tdefer res.Body.Close()\n\tbody, _ := ioutil.ReadAll(res.Body)\n\n\tfmt.Println(res)\n\tfmt.Println(string(body))\n\n}" components: securitySchemes: Bearer-Auth: type: http scheme: bearer description: 'The App API uses a bearer authentication scheme. You can generate a bearer token, known as an **App API Key**, with a defined scope in [your account settings](https://fly.customer.io/settings/api_credentials?keyType=app). [Learn more about bearer authorization in Customer.io](/accounts/settings/managing-credentials). ' ServiceAccount-Auth: x-scalar-ignore: true type: http scheme: bearer bearerFormat: sa_live_ description: 'Transactional send endpoints (`/v1/send/email`, `/v1/send/push`, `/v1/send/sms`, `/v1/send/in_app`, `/v1/send/inbox_message`) also accept a service-account bearer token, prefixed with `sa_live_`. Service-account tokens work across workspaces, so you must pass the target workspace as the `X-Workspace-Id` header on each request. Service-account tokens are intended for testing and one-off sends—for example, using the Customer.io CLI with an AI agent like Claude to verify that a transactional message renders correctly before wiring it into your production backend. **For the production integration that triggers the message from your application, use an App API Key instead**: it''s workspace-scoped, easier to rotate, and has a smaller blast radius. Service-account tokens are server-side credentials. Treat them like any API key—keep them in environment variables or a secret manager, and never embed them in client-side code, mobile apps, or other untrusted contexts. ' bearerAuth: type: http scheme: bearer description: API key passed as a Bearer token