{"server":{"$schema":"https://static.modelcontextprotocol.io/schemas/2025-12-11/server.schema.json","name":"io.github.ni-c/smtp-mcp","description":"MCP server that sends mail over SMTP, gated behind an allowlist and a human confirmation","title":"SMTP","repository":{"url":"https://github.com/ni-c/smtp-mcp","source":"github"},"version":"0.2.0","websiteUrl":"https://smtp-mcp.ni-c.de","packages":[{"registryType":"npm","identifier":"@ni-c/smtp-mcp","version":"0.2.0","transport":{"type":"stdio"},"environmentVariables":[{"description":"Hostname of the SMTP server, e.g. smtp.example.net.","isRequired":true,"format":"string","name":"SMTP_HOST"},{"description":"Port. Defaults to 587 for starttls, 465 for implicit, 25 for none.","format":"number","name":"SMTP_PORT"},{"description":"starttls (default), implicit or none. STARTTLS is required, never opportunistic.","format":"string","name":"SMTP_TLS"},{"description":"Username for SMTP authentication.","isRequired":true,"format":"string","name":"SMTP_USER"},{"description":"Password or app-specific password for SMTP authentication.","isRequired":true,"format":"string","isSecret":true,"name":"SMTP_PASSWORD"},{"description":"The only sender this server will use, e.g. \"Name <person@example.net>\". There is no from parameter.","isRequired":true,"format":"string","name":"SMTP_FROM"},{"description":"Reply-To header on every message, e.g. \"Team <team@example.net>\". Unset means no Reply-To header and replies go to SMTP_FROM. There is no reply_to parameter.","format":"string","name":"SMTP_REPLY_TO"},{"description":"Set to \"true\" to register the sending tools. Defaults to false: the server cannot send until it is set.","format":"boolean","name":"SMTP_ALLOW_SEND"},{"description":"Comma-separated addresses and @domains this server may write to. Required with SMTP_ALLOW_SEND=true; \"*\" allows any.","format":"string","name":"SMTP_ALLOWED_RECIPIENTS"},{"description":"Maximum distinct recipients across To, Cc and Bcc in one message. Default 10.","format":"number","name":"SMTP_MAX_RECIPIENTS"},{"description":"Sliding hourly cap on messages sent. Default 20.","format":"number","name":"SMTP_MAX_SENDS_PER_HOUR"},{"description":"Maximum size of the composed message. Default 10485760.","format":"number","name":"SMTP_MAX_MESSAGE_BYTES"},{"description":"Maximum size of a single attachment. Default 5242880.","format":"number","name":"SMTP_MAX_ATTACHMENT_BYTES"},{"description":"Directory attachments are read from. Unset means attachments are unavailable.","format":"string","name":"SMTP_ATTACHMENT_DIR"},{"description":"Comma-separated content types that may be attached. Defaults to a document and image allowlist.","format":"string","name":"SMTP_ATTACHMENT_TYPES"},{"description":"Text appended below the standard signature delimiter of every message.","format":"string","name":"SMTP_SIGNATURE"},{"description":"File the audit lines are appended to, in addition to stderr.","format":"string","name":"SMTP_AUDIT_LOG"},{"description":"Comma-separated tool names, a prefix with one trailing *, or \"essential\" for the curated preset.","format":"string","name":"SMTP_ALLOW_TOOLS"},{"description":"Comma-separated tool names or prefixes to remove, applied after SMTP_ALLOW_TOOLS.","format":"string","name":"SMTP_DENY_TOOLS"},{"description":"Set to \"true\" to accept self-signed certificates. Prefer a proper internal CA.","format":"boolean","name":"SMTP_INSECURE_TLS"}]},{"registryType":"oci","identifier":"ghcr.io/ni-c/smtp-mcp:0.2.0","transport":{"type":"stdio"},"environmentVariables":[{"description":"Hostname of the SMTP server, e.g. smtp.example.net.","isRequired":true,"format":"string","name":"SMTP_HOST"},{"description":"Port. Defaults to 587 for starttls, 465 for implicit, 25 for none.","format":"number","name":"SMTP_PORT"},{"description":"starttls (default), implicit or none. STARTTLS is required, never opportunistic.","format":"string","name":"SMTP_TLS"},{"description":"Username for SMTP authentication.","isRequired":true,"format":"string","name":"SMTP_USER"},{"description":"Password or app-specific password for SMTP authentication.","isRequired":true,"format":"string","isSecret":true,"name":"SMTP_PASSWORD"},{"description":"The only sender this server will use, e.g. \"Name <person@example.net>\". There is no from parameter.","isRequired":true,"format":"string","name":"SMTP_FROM"},{"description":"Reply-To header on every message, e.g. \"Team <team@example.net>\". Unset means no Reply-To header and replies go to SMTP_FROM. There is no reply_to parameter.","format":"string","name":"SMTP_REPLY_TO"},{"description":"Set to \"true\" to register the sending tools. Defaults to false: the server cannot send until it is set.","format":"boolean","name":"SMTP_ALLOW_SEND"},{"description":"Comma-separated addresses and @domains this server may write to. Required with SMTP_ALLOW_SEND=true; \"*\" allows any.","format":"string","name":"SMTP_ALLOWED_RECIPIENTS"},{"description":"Maximum distinct recipients across To, Cc and Bcc in one message. Default 10.","format":"number","name":"SMTP_MAX_RECIPIENTS"},{"description":"Sliding hourly cap on messages sent. Default 20.","format":"number","name":"SMTP_MAX_SENDS_PER_HOUR"},{"description":"Maximum size of the composed message. Default 10485760.","format":"number","name":"SMTP_MAX_MESSAGE_BYTES"},{"description":"Maximum size of a single attachment. Default 5242880.","format":"number","name":"SMTP_MAX_ATTACHMENT_BYTES"},{"description":"Directory attachments are read from. Unset means attachments are unavailable.","format":"string","name":"SMTP_ATTACHMENT_DIR"},{"description":"Comma-separated content types that may be attached. Defaults to a document and image allowlist.","format":"string","name":"SMTP_ATTACHMENT_TYPES"},{"description":"Text appended below the standard signature delimiter of every message.","format":"string","name":"SMTP_SIGNATURE"},{"description":"File the audit lines are appended to, in addition to stderr.","format":"string","name":"SMTP_AUDIT_LOG"},{"description":"Comma-separated tool names, a prefix with one trailing *, or \"essential\" for the curated preset.","format":"string","name":"SMTP_ALLOW_TOOLS"},{"description":"Comma-separated tool names or prefixes to remove, applied after SMTP_ALLOW_TOOLS.","format":"string","name":"SMTP_DENY_TOOLS"},{"description":"Set to \"true\" to accept self-signed certificates. Prefer a proper internal CA.","format":"boolean","name":"SMTP_INSECURE_TLS"}]}]},"_meta":{"io.modelcontextprotocol.registry/official":{"status":"active","statusChangedAt":"2026-09-07T18:06:20.626217Z","publishedAt":"2026-09-07T18:06:20.626217Z","updatedAt":"2026-09-07T18:06:20.626217Z","isLatest":true}}}