Mailbase is an AI agent for cold outreach. Tell it who to reach — it builds the list, writes and A/B-tests the copy, sends, then reads every reply and works your pipeline. You stay in control: nothing sends until you approve.
Give it an ICP in plain words — “fintech founders, seed to Series A.” It searches your contacts, builds a rule-based segment, keeps the count live and honours every suppression automatically.
See audiencesThe agent drafts two-to-four variants, pilots them on a slice, waits for real confidence (80% / 90% / 95% / 99%), then rolls the winner to the rest of the audience. You approve before anything goes out.
See A/B testingDurable, resumable batches. Every send returns a stable id you can audit. Retries, a dead-letter view, and scheduled sends out of the box — so a flaky provider never costs you a campaign.
See how send jobs workThe agent classifies each reply (hot, warm, cold, objection, out-of-office), drafts the response, and moves the thread along your pipeline. Auto-reply on the actions you trust; everything else waits for you.
Every action maps to a real tool. Side-effects default to “ask”: the agent proposes, you approve. Flip the ones you trust to “auto” and it runs them on its own.
Searches contacts and assembles rule-based audiences from your ICP.
Writes 2–4 variants, pilots them, rolls out the winner on reply rate.
Resumable send jobs with stable ids, retries and a dead-letter view.
Classifies every inbound by intent — hot, warm, cold, objection, OOO.
Moves threads new → qualified → meeting → won, and reports back.
Suppressions, list-unsubscribe and DMARC/SPF/DKIM honoured automatically.
Per-provider health and bounce clustering so issues surface early.
Pick a time. Cancel up to fifteen minutes before it goes out.
One command connects Mailbase over MCP — OAuth-scoped to a single workspace, drafts only. Run it from Claude Code, Cursor or Codex, on our included credits or your own AI key, unmetered.
# Connect your editor in one line$ claude mcp add --transport http mailbase \ "https://mailbase.french-web.com/api/mcp/mcp" # Opening browser for OAuth approval…✓ Connected · 28 tools registered. Ready.
"We replaced two tools with Mailbase. The reply inbox alone paid for it."
"MJML templates that actually render the same in Gmail and Outlook. Finally."
"Real A/B with reply-rate as the metric. Not vanity opens. Sold."
"The MCP integration is the cleanest I've used. Claude Code, no API keys."
"Set up SPF/DKIM/DMARC in under ten minutes. Bounce clustering is killer."
"Auto-classified replies saved my team six hours a week, week one."
"Onboarded the team in an hour. Cmd+K does everything I want."
"Send jobs that don't drop messages. Finally a tool that respects retries."
"We replaced two tools with Mailbase. The reply inbox alone paid for it."
"MJML templates that actually render the same in Gmail and Outlook. Finally."
"Real A/B with reply-rate as the metric. Not vanity opens. Sold."
"The MCP integration is the cleanest I've used. Claude Code, no API keys."
"Set up SPF/DKIM/DMARC in under ten minutes. Bounce clustering is killer."
"Auto-classified replies saved my team six hours a week, week one."
"Onboarded the team in an hour. Cmd+K does everything I want."
"Send jobs that don't drop messages. Finally a tool that respects retries."