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3LT Letter Mail

Give AI assistants hands: send real USPS letters via MCP.

likely compatible

Answered an MCP initialize with no credentials; use auth 'None'.

Rule R2a · what this means · Not tested in Copilot Studio.

Registry namecom.3lgrouptechnology/3lt-letter-mail
Endpoint used for verdicthttps://3lgrouptechnology.com/mcp
Transportsstreamable-http
Auth (Copilot Studio setting)None (open)
Last endpoint check2026-10-20T18:10:31Z · initialize OK
GitHub3LGroupTechnology/3lt-letter-mail
Version1.0.0
Registry updated2026-10-03
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Is this wrong or out of date? Email us. Data built 2026-10-20.