Cross-posting for developers: webhook, REST API, MCP
Publish to channels straight from your code, backend or AI agent.
The problem
You need to post to channels from your service — after a deploy, on an event, on a schedule. Writing and maintaining separate integrations with the Telegram Bot API, VK API and Max API is expensive, and cross-posting between them is a pain of its own.
How Crosslybot solves it
Crosslybot gives you a single webhook endpoint: you send a POST with text and media — the post goes to every configured platform. Idempotency by key, HMAC signature, retry and a sandbox for smoke tests. There's an MCP server for AI agents.
Crosslybot solves publishing to Telegram, VK and Max from your own code. Instead of three separate integrations with platform APIs — a single webhook endpoint: a POST with text and media goes to every configured target of the project.
Idempotency by key, an HMAC signature with replay protection, automatic retry and a sandbox for smoke tests make the integration reliable. For AI agents (Claude, Cursor, Cline) there’s an MCP server with discover and publish tools.
How to set up
Create a webhook endpoint
In the Crosslybot dashboard, create an incoming webhook and attach it to a project with the targets you need.
Grab the token and secret
Copy the Bearer token and HMAC secret. Set up an IP allowlist if needed.
Send a POST
Send JSON with text, media, targets and idempotency_key. The sandbox endpoint validates the payload without real posting.
Wire it into your pipeline
Call the webhook from your backend, CI/CD, cron or a no-code scenario. AI agents — via the MCP server.
What's inside
Webhook IN/OUT
The incoming webhook accepts posts; the outgoing one sends an event about every publication to your system with an HMAC signature.
Idempotency and retry
A repeated POST with the same idempotency_key doesn't create a duplicate. Failed deliveries are retried automatically.
MCP for AI agents
The MCP server gives Claude, Cursor and other agents discover and publish tools — posting straight from the conversation.
Result
One integration instead of three. Publishing to Telegram, VK and Max from any code — with idempotency guarantees and without maintaining platform APIs.
FAQ
How does the webhook differ from MCP?
The webhook is a REST endpoint for backends and no-code scenarios. MCP is a protocol for AI agents: the agent calls discover/publish tools itself. The base is the same — the webhook IN API.
How is the endpoint protected?
A Bearer token, an optional HMAC signature with timestamp verification (replay protection), an IP allowlist and a per-endpoint rate limit.
Can I test without real posting?
Yes. The /v1/sandbox/test endpoint validates the payload and returns a result without publishing — handy for smoke tests in CI/CD.
What plan is needed for the API?
Webhook IN/OUT and MCP are available on the Pro plan and above.
Ready to try?
Connect the bot in 2 minutes. Free plan — no cards, no signup.
