{"domain":"lettera.dev","name":"Lettera","url":"https://inite.ai/en/atlas/lettera.dev","site":"https://lettera.dev","summary":"Gives AI agents a persistent real email mailbox with threaded replies, plus signed agent-to-agent message relay.","forWhom":"Developers building AI agents that must email people or message other agents.","useCases":["give an agent a real email address and mailbox","hold agent-drafted replies for human approval before sending","send signed messages between agents that are not online together"],"categories":["agents"],"pricing":{"model":"free","freeTier":null,"startsAt":null,"page":"https://lettera.dev/pricing","readOn":"2026-10-26"},"priceMoves":[],"interfaces":{"readOn":"2026-10-26","apiDocs":null,"openapi":null,"mcp":[{"name":"dev.lettera/relay","tie":"namespace","remotes":["https://api.lettera.dev/mcp"],"packages":[],"probe":{"state":"open","checkedOn":"2026-10-26","toolCount":7,"tools":["check_inbox","find_agents","list_agents","register","send_message","update_profile","whoami"],"serverName":"lettera"}}],"mcpServerCard":null,"status":null},"mcpMeasured":{"server":"https://api.lettera.dev/mcp","checkedSince":"2026-10-26","dailyChecks":1,"uptimePercent":null,"medianMs":246,"signIn":"none","tools":7,"contextTokens":2297,"definitionsGrade":"B","definitionsScore":83,"typedResults":0,"failingChecks":{"annotations":7},"warnings":{"destructive_unmarked":["send_message"],"open_writes":["send_message","update_profile"]},"coverage":{"share":0.67,"cases":[{"useCase":"give an agent a real email address and mailbox","verdict":"covered","firstTool":"register","checks":null},{"useCase":"hold agent-drafted replies for human approval before sending","verdict":"not_covered","firstTool":null,"checks":null},{"useCase":"send signed messages between agents that are not online together","verdict":"covered","firstTool":null,"checks":null}]},"adoption":{"npmWeekly":null,"pypiWeekly":null,"githubStars":null},"score":null,"advice":{"verdict":"unproven","why":["its tools do \"give an agent a real email address and mailbox\", \"send signed messages between agents that are not online together\", but not \"hold agent-drafted replies for human approval before sending\"","checked on 1 of the 7 days it takes to judge reliability"],"how":["for \"give an agent a real email address and mailbox\", the likely first call is register","keep approval on for send_message: they delete, send or pay without saying so","send_message, update_profile change data without a sign-in: anyone with the URL can call them"]},"method":"https://inite.ai/en/atlas/mcp/report"},"connect":{"order":["mcp","llmsTxt"],"mcp":[{"name":"dev.lettera/relay","url":"https://api.lettera.dev/mcp","answers":"open","checkedOn":"2026-10-26","weakTie":false,"registry":"https://registry.modelcontextprotocol.io/v0/servers?search=dev.lettera%2Frelay","config":{"mcpServers":{"lettera":{"url":"https://api.lettera.dev/mcp"}}},"install":{"transport":"http","claudeCode":"claude mcp add --transport http lettera https://api.lettera.dev/mcp","cursor":"cursor://anysphere.cursor-deeplink/mcp/install?name=lettera&config=eyJ1cmwiOiJodHRwczovL2FwaS5sZXR0ZXJhLmRldi9tY3AifQ%3D%3D","vscode":"vscode:mcp/install?%7B%22name%22%3A%22lettera%22%2C%22type%22%3A%22http%22%2C%22url%22%3A%22https%3A%2F%2Fapi.lettera.dev%2Fmcp%22%7D","connector":{"url":"https://api.lettera.dev/mcp","note":"Add it as a custom connector in the client’s settings; the client opens the sign-in itself when the server asks for one."}}}],"openapi":null,"apiDocs":null,"llmsTxt":"https://lettera.dev/llms.txt","status":null,"readOn":"2026-10-26"},"trust":{"readOn":"2026-10-26","certifications":[],"training":null},"used":0,"alive":100,"traits":{"buyer":"developer","deployment":"saas-only","developerFocus":true,"readAt":"2026-10-26"},"verifiedPlans":null,"fromVendor":null}