hail-sdk

Python SDK for Hail — universal communication platform for AI agents.

Install

pip install hail-sdk

Requires Python 3.11+.

Quickstart

import asyncio
from hail import Client

async def main():
    async with Client(api_key="sk-...") as client:
        # Place an outbound call.
        call = await client.calls.create(
            to="+15551234567",
            system_prompt="You are calling to confirm a reschedule.",
        )
        print("queued", call.id)

        async for event in client.events.tail(id=f"call:{call.id}"):
            print(event.kind, event.payload)

        # Send an outbound email.
        email = await client.emails.create(
            to=["alice@example.com"],
            subject="Welcome",
            body_text="Thanks for signing up.",
        )
        print(email.status, email.from_address)

asyncio.run(main())

api_key defaults to $HAIL_API_KEY; base_url defaults to $HAIL_API_URL (falling back to https://api.hail.so).

API surface

Calls

• client.calls.create(*, to, system_prompt=None, llm=None, from_=None, first_message=None, metadata=None, idempotency_key=None) — originate an outbound call. Pass either system_prompt (mode A) or a full llm block (mode B). idempotency_key defaults to a fresh UUIDv4.
• client.calls.get(call_id) — fetch a single call.
• client.calls.list(*, cursor=None, limit=50, status=None, to=None) — cursor-paginated org list.

Emails

• client.emails.create(*, to, subject, body_text=None, body_html=None, from_=None, cc=None, bcc=None, reply_to=None, conversation_id=None, metadata=None, idempotency_key=None) — send an outbound email. At least one of body_text / body_html is required. from_ is optional; when omitted the server picks a verified sender or auto-mints a hail-mail address (operator-configured). idempotency_key defaults to a fresh UUIDv4.
• client.emails.get(email_id) — fetch a single email.
• client.emails.list(*, cursor=None, limit=50, status=None) — cursor-paginated org list.

Events

• client.events.list(*, id=None, kind=None, cursor=None, limit=100) — one-shot fetch of GET /events. id is a typed <type>:<uuid> string (v1 only supports call:).
• client.events.tail(*, id=None, kind=None, interval_seconds=0.5, follow=True) — async-iterator tail; auto-exits on terminal call status when narrowed to id=call:<uuid>.

Errors

All SDK errors derive from hail.HailError. HTTP-status-coded errors carry .status_code, .detail, and .response_text:

• HailAuthError (401)
• HailNotFoundError (404)
• HailIdempotencyConflict (409)
• HailValidationError (422)
• HailServerError (5xx, after retry budget)
• HailClientError (other 4xx)
• HailMalformedResourceId — local validation of <type>:<uuid> strings
• HailConfigError — no API key supplied or discoverable

Retries

GET/HEAD/PUT/DELETE — and any POST/PATCH carrying an Idempotency-Key — are retried up to 3 times on 5xx with exponential backoff (0.5s, 1.0s, 2.0s) plus jitter, honoring Retry-After when present. Mutating verbs without an idempotency key fail fast on 5xx so a duplicate side effect can't be silently introduced.

License

AGPL-3.0-or-later.