Custom Domains: Publish Your MCP as Your Own OpenAI Plugin

The problem with shared infrastructure

Every MCP server on Shredly lives at mcp.shredly.io/mcp/your-slug. That works great for connecting Claude, Cursor, or any MCP client to your data. But if you want to submit your MCP as an OpenAI plugin, OpenAI requires you to verify ownership of the domain it runs on.

If your MCP lives at mcp.shredly.io, you're verifying Shredly's domain — not yours.

Custom domains

Shredly now lets you point your own subdomain at your MCP server. You add one DNS record, we handle SSL provisioning automatically, and your MCP becomes available at a URL you own.

https://mcp.acme.com/mcp/your-slug

Everything works the same — tools, authentication, OAuth — just under your domain.

Setup via the Shredly MCP

The entire flow is handled through the Shredly MCP itself. No dashboard required.

Step 1: Register your domain

setCustomDomain
  id: <your-mcp-id>
  hostname: mcp.acme.com

This provisions a Cloudflare-managed SSL certificate for your hostname automatically. You get back the DNS record to add:

CNAME  mcp.acme.com  →  mcp-proxy.shredly.io

Step 2: Add the CNAME in your DNS provider

One record. Once it propagates, Cloudflare verifies it and the cert goes live — usually within a few minutes.

Step 3: Confirm it's active

getCustomDomainStatus
  id: <your-mcp-id>

When you see verified: true, your domain is live.

Submitting to OpenAI

OpenAI's plugin submission flow requires verifying that you control the domain. They give you a challenge token during submission — you store it via:

setOpenAiChallengeToken
  id: <your-mcp-id>
  value: openai-challenge-abc123...

Shredly serves it automatically at /.well-known/openai-apps-challenge on your custom domain. OpenAI fetches it, verification passes, and you complete the submission with your MCP URL:

https://mcp.acme.com/mcp/your-slug

Removing a custom domain

deleteCustomDomain
  id: <your-mcp-id>

This removes the Cloudflare hostname, clears the challenge token, and frees the domain to be reassigned.

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Custom domain support is available to all Shredly users. See the Custom Domain Setup guide for the full walkthrough.