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winnr

Cold email infrastructure, handled.

MCPAPINative readiness
About

What is winnr

Winnr handles the infrastructure layer of cold email outreach — bulk account generation, domain registration, DNS configuration, mailbox provisioning, and private SMTP — so teams aren't stitching together separate tools to get a sending stack live. It's built for GTM engineers and founders at SMBs and mid-market companies who run high-volume outbound and need infrastructure that scales without manual DNS work on every new domain. The standout capability is automated domain registration with instant SPF, DKIM, and DMARC configuration, which removes the most error-prone step in spinning up new sending identities. Winnr also exposes a self-serve REST API and a native MCP server, making it callable by AI agents and automation pipelines. That said, Winnr is infrastructure, not a sequencer — it doesn't write copy, manage contact lists, or run campaigns, so you'll still need a separate sending tool like Smartlead or Instantly on top of it.

Capabilities

Key features

Deliverability infrastructure

warmup, spam tests, and sender reputation

Our verdict

Vanderbuild take

Winnr sits at the infrastructure layer of deliverability — it's the plumbing that GTM engineers and founders reach for when they need to spin up dozens of sending domains without touching DNS records manually. The MCP server is the real differentiator here: if you're building agentic outbound workflows in Claude or Cursor, Winnr is one of the few email infrastructure tools you can actually call from an agent natively, making it a credible orchestration layer for automated outbound pipelines. At roughly $1 per mailbox per month, it's affordable for small teams, though costs will stack as you scale sending volume across many domains and accounts. The honest limitation is scope: Winnr is infrastructure only — it has no sequencing, copywriting, or contact management, so it only makes sense if you already have or are building the sending layer on top of it.

Mateusz Sekta
Founder, vanderbuild
The wedge

Agentic stack profile

MCP server
Yes

Live MCP server — agents can call this tool directly.

The tool provides an open-source MCP server that allows AI assistants to manage the full email infrastructure lifecycle, including domain search and purchase, mailbox provisioning, and email warming, all through natural language.

Open MCP →
API
REST

Programmatic access available.

REST API — straightforward to call from any agent or workflow tool. Rate limits and auth vary by plan.

API docs →
Agentic readiness
Native

Built for agents from the ground up.

MCP server + agent-friendly API + at least one autonomous workflow out of the box. The bar for 'Native' is high — only a handful of tools currently qualify.

Stack role
Deliverability

Where this tool slots into an agentic pipeline.

Plays the role of Deliverability in an agentic pipeline. Use it to keep email sending reputation healthy — warmup, spam tests.

Compare

winnr alternatives

Tools that solve a similar problem — compared at a glance.

Answers

Frequently asked questions

Does winnr have an MCP server?

Yes — winnr exposes a Model Context Protocol server. The tool provides an open-source MCP server that allows AI assistants to manage the full email infrastructure lifecycle, including domain search and purchase, mailbox provisioning, and email warming, all through natural language. See the MCP docs at https://winnr.app/mcp.html.

Does winnr have a public API?

Yes — winnr ships a REST API. Docs: https://hub.winnr.app/docs.

How much does winnr cost?

winnr: pricing is seat-based, expect mid tier ($$) spend. Full pricing page: https://winnr.app/.

Who is winnr best for?

winnr is built for GTM Engineer, Founder. Fits SMB (1-50), Mid-market (50-500)-sized teams.

How well does winnr fit an agentic sales stack?

Tier: Native. Has both an MCP server and an agent-friendly API — drops into an agentic stack with minimal glue code.

Quick spec
MCP serverYes
ReadinessNative
Stack roleDeliverability
Pricing
Seat-based
$$
Vendor pricing →
Ideal customer
Growth stage
Growth-stage · Scale-up
Company size
SMB (1-50) · Mid-market (50-500)
Best for
GTM Engineer · Founder