Pipefire MCP server

Pipefire email deliverability tools

Sixteen free email deliverability tools for your AI agent and your terminal. Check a domain's SPF, DKIM, DMARC, MX, BIMI and MTA-STS records, look it up on spam blacklists, read raw email headers, score a cold email and its subject line, and build SPF, DMARC and DKIM records.

Built by Pipefire, cold email software for agencies that sets up and runs outreach for you. The SPF, DMARC and MX checks use the same code Pipefire uses to check its own sending domains, and the cold email checker scores against the same writing rules.

No account. No API key. Nothing you check is stored.

Connect it to your AI agent

It runs as a remote MCP server (streamable HTTP):

https://pipefire.ai/mcp

• LobeHub, Cline, Cursor or any MCP client: add a remote server with the URL above. See llms-install.md.
• Claude Code: claude mcp add --transport http pipefire https://pipefire.ai/mcp
• Gemini CLI: gemini extensions install https://github.com/mikelovatt/pipefire-cli
• Claude and ChatGPT: step by step at pipefire.ai/mcp-server.

Then ask in plain words, for example "Is example.com set up to send email?" or "Score this cold email before I send it".

Pipefire customers: connect the same address in Claude, ChatGPT or Manus and sign in when asked. Your assistant can then read your campaigns, replies, mailboxes and results, draft a new campaign, rewrite a reply draft and pause or resume sending. It never sends an email or launches a campaign: those stay in the Pipefire console behind your click.

Tools

Every tool is read-only. Each one also has a free web version on pipefire.ai.

Tool	What it does	On the web
check_domain_email_setup	MX, SPF, DKIM and DMARC in one go, each with pass, warn or fail and how to fix it	Domain checker
check_dmarc	DMARC policy and reports. Tells you if the domain can be impersonated by email	DMARC checker
check_spf	SPF record, and whether it stays under the 10 DNS lookup limit	SPF checker
check_dkim	DKIM public key. Google Workspace, Microsoft 365 and common selectors are tried	DKIM checker
check_mx	Mail servers and which provider handles the domain's email
check_bimi	BIMI logo record, and whether DMARC is strict enough for it	BIMI checker
check_mta_sts	MTA-STS policy, which forces encrypted delivery of incoming mail	MTA-STS checker
check_blacklists	Whether the domain's sending IPs, or one IPv4 address, are on the major spam blacklists	Blacklist checker
analyze_email_headers	Reads raw email headers: SPF, DKIM and DMARC results, alignment, hops and delays	Header analyzer
check_cold_email	Scores a cold email out of 10 against the rules Pipefire checks its own emails with	Cold email checker
test_subject_line	Scores a subject line out of 10: length, wording that hurts opens, spam triggers	Subject line tester
suggest_sending_domains	Lookalike sending domains, so your main domain never sends cold email	Sending domain generator
guess_email_addresses	Likely email address formats for a person at a company	Email permutator
generate_spf_record	Builds an SPF record from the services the domain sends with	SPF generator
generate_dmarc_record	Builds a DMARC record from a policy and a reports address	DMARC generator
generate_dkim_record	Formats a DKIM public key as the TXT record to publish	DKIM generator

The server also offers a guides resource and two prompts: a full domain audit with a prioritised fix list, and "why did this land in spam?" from a message's headers.

From the terminal

The same tools as a command line app. Needs Node 18 or newer, no dependencies.

npx pipefire check example.com

Command	What it does
pipefire check <domain>	MX, SPF, DKIM and DMARC in one go
pipefire dmarc <domain>	DMARC policy and reports
pipefire spf <domain>	SPF record and the 10 DNS lookup limit
pipefire dkim <domain> [selector]	DKIM public key
pipefire mx <domain>	Mail servers and the email provider
pipefire bimi <domain>	BIMI logo record
pipefire mta-sts <domain>	MTA-STS policy
pipefire blacklist <domain or ip>	Spam blacklist lookup
pipefire headers < headers.txt	Read raw email headers
pipefire subject "<subject line>"	Score a cold email subject line
pipefire email --subject "..." < body.txt	Score a whole cold email
pipefire domains <brand>	Ideas for separate cold email sending domains
pipefire guess <first> <last> <domain>	Likely email address formats for a person
pipefire gen-dmarc <domain> --policy reject --rua you@x.com	Build a DMARC record
pipefire gen-spf google microsoft	Build an SPF record

Add --json to any command for raw output. Install it globally with npm install -g pipefire.

$ npx pipefire dmarc example.com
DMARC check for example.com

DMARC (policy and reports): WARN
  Record: v=DMARC1;p=reject;sp=reject;adkim=s;aspf=s
  Found: Policy p=reject, with no reports address.
  Fix: Add rua=mailto:you@yourdomain so you receive the daily reports that show who sends as you.

How it works

Every tool calls the same code as the free tools at pipefire.ai/tools, through Pipefire's public MCP endpoint. Checks are rate limited per IP. Nothing you check is stored.

About Pipefire

Pipefire is cold email software for agencies that sets up and runs outreach for you. It buys the sending domains, sets up the mailboxes and warms them for 14 days before any cold email goes out. It finds prospects, writes the emails, sends them at a safe daily pace and sorts the replies. You approve every email before it is sent, and your company domain never sends cold email.

• How Pipefire works
• Pricing
• Start with Pipefire

License

MIT