Tasks these servers can do
Is example.com registered, and find an available .com for a bakery name.
Call check_domain_availability on Startup Name Check (https://names.openkrill.app/mcp). Registration status and dates from RDAP for up to five names. Available is indicative, not a reservation. Trademarks are not searched. Some endings have no public RDAP and come back unsupported.
Install steps: ChatGPT, Claude, Cursor, VS Code, Pi.
Is DMARC set up for github.com, and what grade do the published records get?
Call check_email_auth on Domain Mail Check (https://mailcheck.openkrill.app/mcp). SPF, DMARC, DKIM if you pass selectors, MX hosts, a grade from A to F, and a list of fixes. It is a reading of published records, not a penetration test.
Install steps: ChatGPT, Claude, Cursor, VS Code, Pi.
Is my new domain ready to start cold email outreach, and what do I fix first?
Call launch_score on Domain Mail Check (https://mailcheck.openkrill.app/mcp). A score from 0 to 100, a verdict, and the fixes in order. Each rule says if it is a published requirement or only advice, with its source link. It reads public DNS and the registry, sends nothing and cannot see sender reputation.
Install steps: ChatGPT, Claude, Cursor, VS Code, Pi.
Will Gmail and Outlook accept mail from my domain when I send from this IP, and what do I fix first?
Call delivery_check on Domain Mail Check (https://mailcheck.openkrill.app/mcp). One verdict, the top 3 causes with one fix each, and the Gmail, Yahoo and Outlook rules and free blocklists it read, each with a source link. It sends no test message and cannot see sender reputation.
Install steps: ChatGPT, Claude, Cursor, VS Code, Pi.
When does a domain expire, and which registrar published that date?
Call lookup_domain_registration on Domain Mail Check (https://mailcheck.openkrill.app/mcp). Registrar, created, updated and expiry dates, and name servers. Registrant and contact details are not returned.
Install steps: ChatGPT, Claude, Cursor, VS Code, Pi.
What they will not do
A name that is free at the registry can still be premium or trademarked. Mail grades change when DNS changes. Answers are cached for minutes, not for the life of the company.
Where to start
Each link above is a client-specific install page with one call that was checked against the live server. The plain-text list of every server is llms.txt specification. The words MCP, tool and streamable HTTP are defined in the MCP and agent glossary.