Build on sending.ac
Two APIs. One sends and reads mail from mailboxes you already own; the other creates mailboxes for your own customers. They take different keys, and mixing them up is the most common first failure — so every page here says which one it belongs to.
Send and read mail
Section titled “Send and read mail”Point an unmodified Microsoft Graph SDK at our base URL. Your client, your code, your error handling — you change two values and nothing else.
- Base URL
https://api.customers.ac/api/mailbox/v1alpha1- Key
sk_live_…Scope mailbox, live only. Sandbox keys are refused.
Guide · Reference · 4 operations
Provision mailboxes
Section titled “Provision mailboxes”Create users, senders and domains for your end customers. The platform handles Microsoft 365 tenant setup, DNS and mailbox creation, and every write returns an operation you poll.
- Base URL
https://live-api.customers.ac/v1- Key
sac_live_… / sac_test_…Scoped per operation. Sandbox provisions nothing.
Guide · Reference · 17 operations
Not sure which key you have?
Section titled “Not sure which key you have?”Authentication puts both key formats side by side and explains
why the wrong one returns 403 rather than 401.
For agents
Section titled “For agents”The whole site is available as plain text, and both OpenAPI documents are served directly.
/llms.txt |
index |
/llms-full.txt |
everything, including the complete reference |
/llms-small.txt |
prose only, for small context windows |
/specs/mailbox.json |
Mailbox API, OpenAPI 3.1 |
/specs/provisioning.json |
Provisioning API, OpenAPI 3.1 |