# Crier

> The message relay for AI agents. Your agent finishes a task; someone has to hear
> about it. Crier delivers an email, an SMS, or a signed webhook from an
> agent to a person or a system, retrying for hours after the agent's session is gone.
> No account, no mail server, no API key: one x402 micropayment per message.

Operated by Vima Brosta LLC. Contact: contact@vimabrosta.com
Channels offered on this deployment: email, webhook

## Use cases (what to ask for)

- "Email my operator that the report is ready": POST /v1/email
- "Text the customer that their table is confirmed": POST /v1/sms
- "Tell my own backend the job finished, and keep trying if it is down": POST /v1/webhook
- Status reports, confirmations, alerts, handoffs to a human, callbacks to a system that
  the agent cannot stay alive to retry

## Products (pay per message, USDC via x402)

- POST https://crier.vimabrosta.com/v1/email - $0.01 - subject, text (HTML optional), reply_to; footer and unsubscribe link added
- POST https://crier.vimabrosta.com/v1/sms - $0.05 - E.164 number, up to 300 characters; opt-out suffix added. The
  number must have opted in first by texting CRIER to the relay from that handset, so this is for
  people who already expect to hear from your operator, not for reaching someone new
- POST https://crier.vimabrosta.com/v1/webhook - $0.005 - JSON or text body to a public URL, HMAC signed, retried 30 s to 6 h

## Free

- GET https://crier.vimabrosta.com/v1/deliveries/{id} - status: queued, sent, failed, cancelled (Bearer secret)
- DELETE https://crier.vimabrosta.com/v1/deliveries/{id} - cancel before it is sent
- POST https://crier.vimabrosta.com/v1/validate - pre-flight: would this message be accepted (destination, caps, policy)
- GET https://crier.vimabrosta.com/v1/quote - machine-readable pricing and limits
- GET https://crier.vimabrosta.com/.well-known/x402 - payment manifest
- GET https://crier.vimabrosta.com/healthz - service health

## How to pay

Send the request without payment; the HTTP 402 response lists every accepted payment
option (network, asset, amount, payTo) in its accepts array. Pick one, pay, and retry
the identical request with the X-PAYMENT header. Client libraries: @x402/fetch (JS),
x402 (Python).

Accepted rails on this deployment:
- USDC on Base (default rail)
- USDC or native SOL on Solana (same endpoints; pick the Solana option in the 402 accepts list)
- Native ETH and BTC are not accepted: the x402 exact scheme settles token authorizations, so native ETH has no path, and Bitcoin has no x402 rail at all (BTC agent payments use L402, a different protocol).

## Docs

- Full API reference (limits, footers, signature worked example): https://crier.vimabrosta.com/llms-full.txt
- OpenAPI: https://crier.vimabrosta.com/openapi.json
- Pricing JSON: https://crier.vimabrosta.com/pricing.json (human page: https://crier.vimabrosta.com/pricing)
- Terms: https://crier.vimabrosta.com/terms
- MCP endpoint (tool discovery, status, purchase instructions): https://crier.vimabrosta.com/mcp
- For a person who received a message: https://crier.vimabrosta.com/received
- How SMS opt-in works (and why an agent cannot text a stranger): https://crier.vimabrosta.com/sms-opt-in
- Privacy: https://crier.vimabrosta.com/privacy
- Human readable manual: https://crier.vimabrosta.com/manual

## Also by the same operator

- Stumble, persistent watches, wakes, crons, and inboxes for agents: https://stumble.vimabrosta.com/llms.txt
- Umpire, signed verdicts and payment verified reputation: https://umpire.vimabrosta.com/llms.txt

## Conduct

Crier relays. It does not choose recipients, does not read what it carries,
and drops the destination and content once a delivery is final. Every email names the
relay and carries an unsubscribe link; every SMS carries an opt-out suffix; a destination
that bounces, complains, opts out, or unsubscribes is refused to every future sender,
before payment.