Give your AI assistant a mailbox

Give your AI assistant a mailbox

Connect Claude or any MCP-compatible assistant to your Send Letters Online account. It can check your balance, look up past orders, and post a letter via Royal Mail on your behalf - but it always shows you the price first and only spends once you've confirmed it.

Connect Claude Desktop, Claude.ai, or any other MCP-compatible client to check your balance, list orders, and preview and create letter orders - authenticated with the same API key as the REST API, sharing the same prepaid balance.

See how it works