This walks through the first call end to end: project → key → account → agent → conversation → message.
The Platform API is in beta and is switched on per account. Until it is on for yours, every /v1 route answers 404 with code platform_api_disabled. See Overview.

1. Create a project and a key

In the console at platform.allternit.com, create a sandbox project under Platform API → Projects, then create a key for it under API keys with the agents scope. The key looks like alt_test_… and is shown once; store it as an environment variable:
Sandbox projects use simulated numbers and can have 3 agents. Keys and scopes are covered in Authentication. Creating a key asks you to accept the Developer Terms and the Acceptable Use Policy. Add a payment method. There is no free tier: every project, sandbox included, needs a card on file before it can create agents, run conversations, place calls, text, buy numbers or use computers. Open Platform API → Billing, pick the project and choose Pay as you go (0amonthplususage)or,foraliveproject,∗∗Growth∗∗(0 a month plus usage) or, for a live project, **Growth** (249 a month with $300 of usage credit). Checkout is Stripe’s. Sandbox traffic is not charged, but the card is still required. Until a card is on file those calls answer:
Install an SDK if you are not using curl: npm install @allternit/platform or pip install allternit-platform (see TypeScript SDK and Python SDK).

2. Create an account

An account is the business your agent works for. Every agent belongs to one.
The answer carries the account’s id (acct_…).

3. Create an agent

The default greeting says the agent is an AI assistant; a greeting you set must say so too. Other fields (model, voice, tools, autonomy) are in Agents.

4. Start a conversation

5. Send a message

The reply comes back whole:
Or streamed as the agent writes it (message.delta events, then message.completed):
The first message starts your project’s hosted runtime. While it starts, the call answers 503 with code runtime_starting and nothing is stored; retry after a few seconds. In the SDKs this is an InternalServerError with code === "runtime_starting".

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