Sendmux CLI
Sendmux CLI gives a developer or agent terminal access to Sendmux's Management, Mailbox and Sending APIs. It is an interface to an email service, rather than a model that writes messages. Its documentation covers installation, authentication profiles, structured output and request-safety flags.
Choose credentials for the operation
The CLI supports OAuth connections with explicit scopes, mailbox-compatible API keys and team-scoped management keys. OAuth sign-in opens a browser for consent, while stored profiles keep credentials in local files with restricted permissions. Review the scopes you approve; reading messages and sending email are different permissions.
The CLI checks whether a key or profile fits the command surface before making a request. A management key cannot substitute for a sending credential. For automation that supplies its own access token, the documentation says the CLI does not refresh that token. Plan how the automation handles expiry rather than assuming a saved environment value stays valid.
Installation options include npm, Homebrew, Linux Snap packages and standalone releases for supported operating systems. Verify the available release for the computer running your automation before deciding how to distribute it.
Register an agent inbox without granting it unlimited access
An agent can register an address at myagent.mx without an existing Sendmux account or API key. The documentation says registration saves a durable read credential in a private local profile and does not print it. That credential supports reading and receiving mail.
Sending still requires the owner's acceptance and approval. The CLI then exchanges the durable credential for a one-hour sending token. The documented inbox capacity is capped at 500 MiB before approval; sending approval raises it to at least 5 GiB. Treat these as separate controls, not evidence that a newly registered agent may email anyone.
Make automation observable and safe to retry
Commands can return machine-readable JSON. Request bodies may come from an inline value or a file, and parameters are validated before the request. Idempotency and conditional-request flags are available when the underlying API operation supports them. Check command help rather than assuming every operation accepts every safety flag.
The service overview makes an important delivery distinction: managed Amazon SES is for transactional email only. Marketing, newsletters and bulk promotional sends require your own provider. Respect that restriction when connecting an agent to outbound workflows.
Test against a controlled mailbox before giving an automation access to client conversations. Confirm both the messages it can read and the recipients it can send to, and keep credentials out of logs and shared scripts.