Concepts
A gateway is the address AI clients use to reach your APIs.
The terms
| Term | What it is | Where it lives in the portal |
|---|---|---|
| API | An API Faustine has analyzed: its operations, their schemas, which ones write, how it authenticates. | APIs |
| Operation | One thing a client can call, such as crm.contacts.create. An operation reads or writes, and can require confirmation. |
The API's Operations tab |
| Gateway | Serves one or more APIs at one URL, over MCP and REST. | Agent Gateway |
| Environment | A copy of the gateway's configuration with its own URL. Every gateway has Production. | The environment button in the gateway header |
| Credential | Who can call one environment. An API key or a gateway user. | The gateway's Access tab |
| Client | The program that connects: Claude, ChatGPT, Claude Code, Cursor, VS Code, n8n, the CLI or your own code. | The gateway's Connect tab |
The order
A gateway is set up in the same order every time:
- Analyze an API. A gateway can only serve an API that exists in APIs.
- Create a gateway and choose the operations it serves. Every operation starts exposed, except recipes and deprecated operations.
- Create an API key or a gateway user.
- Connect a client.
- Read the logs. Each request has an ID that starts with
req_.
The gateway's Overview tab shows these steps with their state until all of them are done. The state is per environment, because each environment has its own APIs, credentials and traffic.
Where each setting is made
Settings live at four levels. A setting made at one level cannot be changed at another.
| Level | What is set there |
|---|---|
| The API | Whether an operation reads or writes, and whether it requires confirmation. These apply to every gateway that serves the API. |
| The environment | The served APIs, their versions and connections, the exposed operations, the policies (MCP mode, limits, restrictions, repeated writes), the API reference, the variables and the log settings. |
| The credential | Its scope, whether it is read-only, what it does with operations that require confirmation, and limits lower than the environment's. A credential belongs to one environment. |
| The gateway | The name, the slug, Published or Paused, and the list of environments. These are in the Settings tab. |
Operation keys
An operation has a key of the form <namespace>.<operation>, where <namespace> is the API's namespace. crm.contacts.create is the operation contacts.create of the API crm. The key appears in scopes, in logs, in the REST URL (…/api/crm/contacts.create) and in Code mode scripts (sdk.crm.contacts.create(input)).
Next steps
- Create a gateway: start with the wizard.
- Environments: what an environment owns.
- Operations: how the analysis classifies an operation.
- Connect clients: which clients sign in and which carry a key.
Last updated November 13, 2026