ChatRail

ChatRail is a REST API that sends, receives and auto-replies to WhatsApp messages through a linked WhatsApp account instead of Meta's official Business Platform, so there is no Business Manager approval queue, no message templates and no per-message fee.

What is ChatRail?

ChatRail is a developer-facing WhatsApp messaging API: you make a JSON HTTPS request with a bearer token, and ChatRail delivers the message from a WhatsApp number you paired by QR code. Incoming messages, delivery status changes and connection events come back to your endpoint as signed webhooks. It is a hosted web workspace with a dashboard for connections, schedules, logs and a sandbox, and it speaks JSON in and JSON out with no SDK to install. The source page does not name a parent company behind the product.

What makes ChatRail stand out?

• Linked-device connection — you pair a number by scanning a QR from the dashboard, so the number keeps working normally on its phone and no Meta Business verification or template review is required.
• Context-aware AI replies — attach a context object to a send and, with ai_replies enabled, follow-up questions are answered from that attached data only; draft mode (human approves each reply) is the default.
• Per-recipient delivery state — messages report sent, delivered, read or failed, with a named failure reason such as not_registered or media_too_large rather than a red dot, and results are exportable as CSV.
• Signed webhooks with idempotency — every event carries an X-ChatRail-Signature header and an idempotency key, covering message.delivered, message.read, message.received and session.disconnected.
• Automatic retries — failed webhook deliveries are retried on a backoff (for example 0s, then 4s, then 16s) and the outcome is recorded.
• Number checks before sending — you can verify a number is registered on WhatsApp before sending, protecting the sending number from wasted attempts.
• Media both ways — photos, voice notes and documents arrive with a workspace-scoped download_url; group participants can be listed by name and id only, never by identity.
• Runaway-loop guardrails — a hard ceiling of 10 messages per person per 5 minutes, queued rather than dropped messages when a session disconnects, and re-pairing by QR.

Who should use ChatRail?

• Backend and automation developers who want to fire WhatsApp alerts from existing code or tools such as Make, n8n, Zapier, Supabase or Retool without adopting an SDK.
• Property managers and schedulers sending rent-due reminders on the 1st, renewal notices 30 days out, or appointment reminders 24 hours ahead to lists of 20 to 400 recipients.
• Agencies and multi-client teams that need per-client webhooks, separate credentials and up to five connected numbers under one workspace.
• Support and ops teams who want replies to alert messages answered from structured data they attach at send time.

What can you do with ChatRail?

• Property alerts: attach a listing payload such as listing_4821.json to a send, so a tenant replying "Does it have parking?" gets an answer drawn from that listing data.
• Billing and invoice follow-up: attach invoice totals, paid-to-date and late-fee rules, then let the customer's question about paying after the due date be answered from that context.
• Operations alerting: deliver monitored-event alerts to a private WhatsApp group or list, with per-recipient read and delivered counts for the batch.
• Media capture workflows: pull photos and documents shared in a WhatsApp group and route them to Google Drive or Dropbox via the file's download link.

How does ChatRail work?

You pair a WhatsApp number by scanning a QR code from the dashboard (Settings, then Linked devices, then Link a device); the phone keeps working as normal. You then POST your first message to the messages endpoint with a JSON body naming the connection, the recipient and the text, plus an optional context object and schedule. Replies and delivery updates arrive at your endpoint as signed webhooks, and you watch each message land in the log.

Pricing

ChatRail is freemium. Sandbox costs nothing and includes 1 connected number, 500 messages a month, basic API and webhooks, and a 7-day message log. Core is for production alerts, Core + AI adds context-aware replies with 10,000 AI replies a month and MCP tools, and Team covers 5 connected numbers, 50,000 AI replies and per-client webhooks. Extra numbers cost $8/month, annual billing gives two months free, and bringing your own model key removes the AI reply cap on the paid AI tiers.

FAQ

Is ChatRail an official Meta integration?

No. ChatRail connects as a linked device to a regular WhatsApp account rather than through Meta's WhatsApp Business Platform. That is what removes templates and the approval queue, but it also means a session can be disconnected and your account remains subject to WhatsApp's own policies, so ChatRail monitors session state and flags numbers needing re-pairing.

Do I need my own AI key?

No. Core + AI includes 10,000 AI replies a month and Team includes 50,000, running on ChatRail's model. You can bring an OpenAI-compatible, Anthropic, OpenAI, Google Gemini or DeepSeek key, or point at a self-hosted base URL, if you want a different model or uncapped replies.

Can I use ChatRail without AI replies?

Yes, and that is the default. Messaging, scheduling, webhooks and connection management are the product; AI replies are a switch you turn on per connection, and the context object is only sent to a model provider when that switch is on.

What happens when a number disconnects?

You receive a session.disconnected webhook, the connection is flagged in the dashboard, and queued messages hold rather than fail silently. Re-pairing is a QR scan, and you can re-pair one number without affecting the others.

Is there a free tier?

Yes. The Sandbox plan includes 1 connected number and 500 messages a month with no expiry, a basic API and webhooks, and a 7-day message log, so you can test before upgrading to a production plan.