MCP TOOL
cubeshell.email.verifyEmail Verification
Checks whether one email address is deliverable. Use it when you already have an address and want its risk checked — it does not find an unknown address, send email, or verify a list.
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Live execution
The active route performs a live mailbox check. The response discloses
execution.mode: "live" and includes the durable operation, credit movement and receipt.Request
Workspace identity comes from the authenticated MCP connection, not from the call arguments — there is no workspace field to set.
| Parameter | Type | Description |
|---|---|---|
request_idrequired | string | Your own idempotency key, 1–200 characters, no leading/trailing whitespace or control characters. Replaying the same request_id with the same input returns the original result and does not charge again. |
quote_onlyrequired | boolean | Must be exactly false in this version. Quote-only preview without executing is not available yet. |
input.emailrequired | string | The address to check. Up to 320 characters, valid email format. Trimmed and lowercased before matching, so " Deliverable@Example.com " and "deliverable@example.com" are the same input. |
max_microcredits | integer | Optional ceiling. If the authoritative price exceeds this, the call is rejected with PRICE_LIMIT_EXCEEDED before anything is charged. |
Example call
Sent as a normal MCP tools/call once your client is connected.
tools/call
{
"name": "cubeshell.email.verify",
"arguments": {
"request_id": "verify-2026-07-17-001",
"quote_only": false,
"input": { "email": "deliverable@example.com" }
}
}Result
On status: "succeeded", the result field holds the verification outcome.
| Parameter | Type | Description |
|---|---|---|
result.status | "deliverable" | "undeliverable" | "risky" | "unknown" | unknown means Cubeshell could not reach a confident answer — it is never billed (see Billing below). |
result.confidence_basis_points | integer (0–10000) | 10000 = 100% confidence. |
result.evidence.syntax_valid | boolean | Whether the address is syntactically valid. |
result.evidence.domain_has_mx | boolean | Whether the domain has a mail-exchange record. |
result.evidence.mailbox_check | "accepted" | "rejected" | "catch_all" | "blocked" | "not_attempted" | "unknown" | Outcome of the mailbox-level check, when one was attempted. |
Errors
A rejection never creates an operation or a charge. See Error Codes for the full list; the ones you will see most from this tool are INVALID_INPUT (malformed email, reused request_id with different input, or quote_only: true) and INSUFFICIENT_CREDITS.