Spin up ephemeral test inboxes for email integration tests

Short summary

Most teams skip real email testing because asserting on received mail from a test runner is hard. This post introduces Nylas Agent Accounts — disposable mailboxes created via a single API call per CI run, with no OAuth and clean teardown — as ephemeral test fixtures for send and receive integration tests. It covers setup, quota limits, and how this approach provides structural isolation that mocks and shared Gmail accounts cannot.

• •Agent Accounts are Nylas grants created without OAuth, usable with all grant-scoped endpoints
• •Each CI run gets an isolated, real mailbox that sends and receives actual email for honest assertions
• •Provision per run not per test to avoid quota limits; always tear down after the job finishes

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