Mails is an API service that provides powerful email validation capabilities to help maintain a clean and effective email list.
Mails is an API service that provides powerful email validation capabilities to help maintain a clean and effective email list. On Nagent, Mails.so is exposed as a fully-configurable email integration that any agent can call — 3 actions, and API key authentication. No code is required to wire Mails.so into your workflow — connect it once via the External Integrations panel and reuse it across every agent you build.
Agent builders use Mails.so to automate the kinds of tasks email teams previously handled manually. Concrete examples — each one is a single agent step in Nagent — include:
Every action and trigger is paired with a structured input/output schema (visible in the sections below), so when you wire Mails.so into Helix — our agentic agent builder — the editor knows exactly what each step expects and produces. Configure once, deploy anywhere across your Nagent agents.
Every operation an agent can call against Mails.so, with input parameters and output schema. Drop these into any step of an agent built in Helix.
MAILS_SO_RETRIEVE_BATCH_RESULTSTool to retrieve results of a bulk validation job. Use after submitting a batch and you have its ID.
Input parameters
Unique identifier for the batch validation job
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
MAILS_SO_VALIDATE_BULK_EMAILSTool to validate multiple email addresses in bulk. Use when you need to confirm deliverability of a list of emails at once.
Input parameters
List of 1–1000 email addresses to validate
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
MAILS_SO_VALIDATE_SINGLE_EMAILTool to validate a single email address. Use when you need to check deliverability and quality details before sending an email.
Input parameters
The email address to validate.
Output
Data from the action execution
Error if any occurred during the execution of the action
Whether or not the action execution was successful or not
No publicly available marketplace agent is found using this tool yet. There are 79 agents privately built on Nagent that already use Mails.so.
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Connect Mails.so to any Nagent agent in minutes — no API key management, no boilerplate. Just configure and deploy.
The five questions agent builders ask before adopting a new integration.
Open the External Integrations panel inside Nagent (app.nagent.ai/externalIntegration), find Mails.so, and click "Connect Now." You'll authenticate with an API key — Nagent handles credential storage and refresh automatically. Once connected, Mails.so is available to any agent in your workspace.
No. Nagent provides no-code integration for every tool. Once Mails.so is connected, you configure its 3 actions directly in the agent builder UI — no API calls, no boilerplate, no schema management.
Helix — Nagent's agentic agent builder — lets you drop Mails.so steps into any workflow visually. Pick an action (e.g., one of those listed above), fill in the inputs (Helix knows the required vs. optional schema for each parameter), and connect it to upstream/downstream steps. Triggers run as the entry point of an agent, so when a Mails.so event fires, the agent kicks off automatically.
Every Mails.so action and trigger ships with a fully-typed schema — input parameters with name, type, required flag, and description, plus the output payload shape. The schemas are documented in the sections above. Helix uses these schemas to validate your configuration at build time and to type-check the data flowing between steps.
Yes. While Mails.so ships with 3 pre-built email actions, you can layer custom logic around them inside Helix — pre/post-processing steps, conditional branches, retries, or stitching Mails.so together with other connected tools. For deeper customization, talk to our team about Nagent's Agentic AI Lab — forward-deployed engineers who build Mails.so-based workflows tailored to your business.