mailbox-validator

name

mailbox-validator

description

MailboxValidator provides real-time email address verification and list-cleaning services—via easy RESTful APIs or bulk uploads—to detect invalid, disposable, free, role-based and unreachable emails, helping businesses reduce bounce rates, improve deliverability, and maintain higher-quality marketing data. Read and write Mailbox Validator data through One: emailvalidation, emaildisposable, emailfreeprovidercheck and more, 4 actions with real parameter documentation. Use whenever the user asks to look something up in Mailbox Validator, create or update a record there, or build code against the Mailbox Validator API.

Mailbox Validator through One

MailboxValidator provides real-time email address verification and list-cleaning services—via easy RESTful APIs or bulk uploads—to detect invalid, disposable, free, role-based and unreachable emails, helping businesses reduce bounce rates, improve deliverability, and maintain higher-quality marketing data.

One exposes Mailbox Validator through four MCP tools. The table below carries real action ids from One's knowledge base, so for a common operation you can skip search and go straight to reading the action's parameters.

How to run an action

1. Find the action in the table below, or call search_one_platform_actions with platform mailbox-validator if it is not listed.
2. Call get_one_action_knowledge with the action id. Do this every time, including for actions in this table. The table gives you the id, not the parameters.
3. Call execute_one_action with parameters copied from that knowledge.

Never guess a parameter name, a body field, or an enum value. The knowledge has the real schema, and a guessed field is either a 400 or a silent write of the wrong thing.

Before you start

Call list_one_integrations once and confirm Mailbox Validator is connected. If it is missing, the user has not connected it: say so and point them at https://app.withone.ai rather than reaching for raw HTTP.

Each connection carries an access field. If it reports {"policy": "methods", "methods": ["GET"]} the agent is read-only here, so plan a read-only answer instead of attempting a write that will be refused.

Before a write

Creates, updates, deletes and sends land on a real Mailbox Validator account and cannot be recalled. State the action and the specific target in one line before the first write in a task, and let the user stop you. Reads need no confirmation.

Actions

EmailValidation

Action	Method	Path	Action id
Test Connection	GET	/v2/validation/single?email='test'	conn_mod_def::GJd9wr5yUbA::vxIyfL1OQL2bqEjeq8q60g
Validate a Single Email Address	GET	/v2/validation/single	conn_mod_def::GJd7D2uuxCg::MxQG0BWySJ20sHHOU_RqtA

EmailDisposable

Action	Method	Path	Action id
Check if an Email Address Is Disposable	GET	/v2/email/disposable	conn_mod_def::GJd7D9htb2A::g4fHV2T6QP2pyuhk20Xjcw

EmailFreeProviderCheck

Action	Method	Path	Action id
Check if an Email Address Is from a Free Email Provider	GET	/email/free	conn_mod_def::GJd7EFdxE0g::foxiQOTTTpCkdjHJIoX5SA

When a call fails

The error comes from Mailbox Validator, not from One. A 400 or 422 means your parameters do not match the schema, so re-read the knowledge and fix the field. A 401 or 403 means the connection needs re-authorizing, which no retry will fix. A 404 means the id is not on this account. A 429 means slow down. Never retry a write more than once: the first attempt may have landed.

Full catalog: https://www.withone.ai/knowledge/mailbox-validator

Integration knowledge by One (withone.ai), licensed under One-Knowledge-1.0. Attribution must be preserved in derivative works.