verify_email(address) -> { address, verdict: valid | invalid | risky, reason }

{"name": "verify_email",
 "description": "Check whether an email address can receive mail. Returns a verdict of
   \"valid\" (well formed and not flagged), \"invalid\" (malformed, mail cannot be
   delivered), or \"risky\" (well formed but on a disposable provider, so delivery is
   unreliable), together with the reason the verdict was reached. Accepts one address
   per call.",
 "inputSchema": {"type": "object", "additionalProperties": false,
                 "properties": {"address": {"type": "string"}},
                 "required": ["address"]},
 "outputSchema": {"type": "object",
   "properties": {
     "address": {"type": "string", "description": "The address that was checked, lowercased."},
     "verdict": {"type": "string", "enum": ["valid", "invalid", "risky"],
                 "description": "valid: syntax is well formed and the address looks
                   deliverable. invalid: syntax is malformed, the address cannot receive
                   mail. risky: syntax is well formed but the domain is a disposable
                   provider, so delivery is unreliable."},
     "reason":  {"type": "string", "description": "Which rule produced the verdict."}},
   "required": ["address", "verdict", "reason"]}}

{"address": "alice@example.com",    "verdict": "valid",   "reason": "syntax is well formed and the domain is not flagged"}
{"address": "not-an-email",         "verdict": "invalid", "reason": "address does not match the expected email syntax"}
{"address": "alice@mailinator.com", "verdict": "risky",   "reason": "mailinator.com is a disposable email provider"}

uv sync
uv run python mock_server.py    # mock backend       on 127.0.0.1:8000
uv run python mcp_server.py     # MCP server

claude mcp add --transport http tvram-email-verification http://127.0.0.1:8001/mcp