"Services or tools available for free without requiring an API key" matching MCP connectors:
GET /v1/connectors — MCP directory API referenceMatching Connector Tools:
Connect AI assistants to Mailercloud, the email marketing platform. Tools to manage campaigns, contacts, lists, templates, automations, webhooks, senders, and transactional email — plus AI-powered campaign analysis, deliverability audits, and engagement insights.
Email posture for any domain: can it receive mail, can it be spoofed? MX, SPF and DMARC.
Crevio's MCP server lets an agent run a real online business, not just read from one. It exposes a delegation surface (ask_crevio, start_task, wait_for_run, send_message, resolve_approvals) plus code_search and code_execute for calling the full Crevio REST API - products, customers, orders, email, socials, and sites.
Read-only Amazon SES observability: search events, inspect bounces, pull delivery stats.
Teaches AI to write HTML email that renders in Outlook, Gmail, and Apple Mail. 19 rules, 6 comps.
Analyze, audit, fix and diff HTML, MJML, Maizzle and React Email across 21 email clients.
Send WhatsApp, SMS, email or voice to real businesses. TCPA/GDPR/CASL gate built in.
Manage Subscribers, Broadcasts, Sequences, Automations, and reporting in Mailrith.
DNS and email security scanner with 79 MCP tools for SPF, DMARC, DNSSEC, SSL, and brand audits.
Email for AI agents: send, read replies as threads, run campaigns, with per-key limits.
Email OS for agents - real-inbox search, triage, commitments, and a verifiable BEC hard-stop.
Register, renew, transfer, and manage domains, DNS, VPS, and email with 102 tools. By OSIR.
Render markdown into email-safe HTML, lint drafts for deliverability problems, and preview emails.
Emailable MCP — wraps the Emailable email verification API (emailable.com)
Keyless email checks: disposable, role, and free-provider detection, MX, and typo suggestions.
Coldrig — cold-email infra run by your agent: 28 MCP tools, live sending, free sandbox. $99/mo.
Let ChatGPT, Claude & Cursor use your Mac: email, calendar, iMessage, Teams, files. Local, free.
DMARC-safe email forwarding for agents: aliases, DNS health checks, and MCP tools on your domains.
Prepaid email-verify credits for MCP agents via Stripe Link.
7 outreach, sequencing, call-coaching and CRM-hygiene skill products. 6 of 8 free.
