Truelist — Claude Code MCP server: what it does, how to install
Validates email deliverability and flags spam traps directly from assistant prompts. Helpful when cleaning subscriber lists in code editors.
claude mcp add --transport http mcp https://api.truelist.io/mcpWhat Truelist does
Truelist MCP server connects email address verification directly to your coding assistant. It adds three tools to the model: validate_email for checking individual mailboxes, validate_emails for processing batches of up to 50 addresses, and check_account to query subscription details.
During inspection, the tool examines domain records and mailbox availability. It checks syntax, inspects MX records, contacts the mail server over SMTP, and flags temporary domains or spam traps. If an email domain accepts all mailboxes indiscriminately or applies temporary greylisting, the tool reflects this in dedicated sub-state values.
The server requires a valid TRUELIST_API_KEY environment variable to initialize. Because batch verification processes emails concurrently, sending large arrays can trigger rate limits, which the client handles using automatic exponential backoff retries.
What it helps with
- check if a single email address is deliverable
- filter disposable mailboxes and spam traps in batches up to 50 items
- verify MX records and test mailbox existence via SMTP
- check current Truelist subscription tier and account details
Example prompts for the agent
- Check if
[email protected]can receive mail and show verification details. - Validate this batch of email addresses from
leads.jsonusing Truelist. - Check my Truelist account status and plan details.
How to install Truelist
1Platform CLI: remote server
claude mcp add --transport http mcp https://api.truelist.io/mcp2Platform CLI
claude mcp add --env TRUELIST_API_KEY=<TRUELIST_API_KEY> --transport stdio truelist -- npx -y truelist-mcpReplace <…> with your own values
1Platform CLI: remote server
codex mcp add truelist --url https://api.truelist.io/mcp2Platform CLI
codex mcp add truelist --env TRUELIST_API_KEY=<TRUELIST_API_KEY> -- npx -y truelist-mcpReplace <…> with your own values
Config file
{
"mcpServers": {
"truelist": {
"url": "https://api.truelist.io/mcp"
}
}
}{
"mcpServers": {
"truelist": {
"command": "npx",
"args": [
"-y",
"truelist-mcp"
],
"env": {
"TRUELIST_API_KEY": "<TRUELIST_API_KEY>"
}
}
}
}Replace <…> with your own values
Config file
{
"servers": {
"truelist": {
"type": "http",
"url": "https://api.truelist.io/mcp"
}
}
}{
"servers": {
"truelist": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"truelist-mcp"
],
"env": {
"TRUELIST_API_KEY": "<TRUELIST_API_KEY>"
}
}
}
}Replace <…> with your own values
1Platform CLI: remote server
gemini mcp add -t http truelist https://api.truelist.io/mcp2Platform CLI
gemini mcp add -e TRUELIST_API_KEY=<TRUELIST_API_KEY> truelist npx -y truelist-mcpReplace <…> with your own values
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Truelist
How to install Truelist in Claude Code?
Run claude mcp add --env TRUELIST_API_KEY=<TRUELIST_API_KEY> --transport stdio truelist -- npx -y truelist-mcp with your actual key. Alternatively, connect via HTTP transport using claude mcp add --transport http truelist https://api.truelist.io/mcp.
What does Truelist do?
It gives your AI tools to verify single emails, batch-check lists up to 50 addresses, and inspect account status. The server returns deliverability states, detects spam traps, and flags disposable services.
Can Truelist MCP be used on a free plan?
Yes, Truelist provides a free tier with 100 standard verifications and 10 enhanced credits without a credit card. You only need to register and generate an API key.
