An API key and an MCP connection are different doors
The Public API sends texts with a bearer key. MCP lets an AI app act in your account after you approve it. Live keys wait on an approved 10DLC registration.
Settings, Developers, Open developer workspace is where both doors live. API reference sits next to it. The docs site is docs.statxt.com. API Keys, the Console, Logs, and Recipes (TypeScript, Python, and cURL) are the API side. MCP is the other.
Test keys do not text anyone
Create a key with a label, an environment, and a scope. Test keys are for building. Those sends are not delivered and do not use credits. Live keys send real texts, and they stay unavailable until 10DLC registration is approved. Personal keys see only your data. Organization keys see the team's data, and only the owner can create them. Copy the key when it is shown. It is not shown again. Keys start with intx_public_test_ or intx_public_live_. Send them as Authorization: Bearer, or you will get an error instead of a message.
One labeled key per integration means you can revoke a leaked key without breaking the others. Revoke key stops that key immediately.
The first request
POST https://app.statxt.com/api/v1/messages. to is the recipient. body is the text, up to 1,600 characters. Send from one of your numbers with either from or from_phone_number_id, not both. A personal key can only send from a number assigned to you. An Idempotency-Key header makes a retry safe. Reuse the same key and Statxt will not send the message twice.
A successful call returns 202 Accepted with the message id and status. Status then moves through values such as queued, sent, and delivered, or failed and undelivered. Logs in the workspace shows the request. Errors include a code and a message, listed on the Errors tab. Webhooks, on the Webhooks tab, push status updates if you do not want to poll. The Console can send the same request from the browser before you write any code.
MCP does not use that key
MCP is how an AI app such as Claude, Codex, or Cursor uses Statxt after you sign in and approve access. The endpoint is https://mcp.statxt.com/mcp. Claude wants it added as a connector. Codex has an install command. Any other MCP client uses the endpoint directly. The consent screen is Approve & reconnect. You can Disconnect later under Settings, Developers, MCP, and connect again for a fresh approval.
What the assistant can reach follows your role. Owners and admins get organization access. Managers and members get their personal workspace. Viewers are read-only. The tools can preview a message and check compliance before a send. Ask for that check on anything a customer will see.
The click-by-click version lives in the API & MCP guide.
Walk through it in the product
The guides cover these same workflows step by step, with the screens you will actually use.