Guide
How to monetize an MCP server
Your free tier costs real money. Here are the options, and which one fits which kind of server.
A hosted MCP server costs real money to run, and most of the people and agents using it will never pay. There are four honest ways to cover that. They suit different servers, and you can combine them.
Charge for access
Give out API keys and sell a paid plan, with a free tier for trying it. This is the simplest route, and it suits tools used by teams at work. The downside is friction: every new user has to sign up before an agent can call your server.
Bill by usage
Meter each call and charge for what is used. This suits expensive tools, such as ones that run models, browsers or paid data sources, because your income grows with your costs. Agents need a way to pay, so you either bill a key holder monthly or accept per-request payment through a protocol such as x402.
Sell the tool to agents directly
List it in places where agents can find and buy tools, and take payment per request. It removes signups, but the market is young, so don't expect much volume yet.
Carry a labelled sponsored line
Keep the free tier free, and add one clearly labelled sponsored line to your tool's results. It suits popular free tools whose users won't pay. Done badly it is prompt injection, so the rules matter:
- Put it in a separate, labelled field, never inside the result.
- Write it for people. It must never give instructions to a model.
- It must never change the result itself.
- Turn it off for paying users, and let people opt out.
- Follow the host's rules, and your own venue policy.
How to choose
- Teams use it at work
- Charge for access.
- Each call costs you real money
- Bill by usage.
- Agents call it without a person involved
- Try per-request payment.
- Lots of free users, and people read the output
- Carry a labelled line.
What to watch out for
Sponsored lines only have value when a person sees them. Many tool results go straight to a model and never reach a screen, and some hosts may hide extra fields. Advertisers pay for people, so count only what was really shown, and don't count agent traffic as reach.
If you do carry ads, read how AI ad impressions can be verified, because your numbers will need to stand up to checking.
Run a free MCP server?
Talk to us about carrying one labelled line, and what it could cover.