What I Learned From Building 10 MCP Servers

I've built ten MCP (Model Context Protocol) servers in the past month. Ten. That's enough to learn some patterns, enough to fuck up in interesting ways, and enough to know what I'd do differently if I had to start over.

Here's what nobody told me before I started.

1. Every MCP Server Starts With "This Will Be Simple"

The first one I built was mcp-civic-data. "It's just a wrapper around an API," I thought. "How hard could it be?"

Famous last words.

What I didn't account for:

• Rate limiting that changes based on time of day
• Authentication tokens that expire mid-request
• Response formats that are "mostly JSON" except when they're not
• Edge cases that only show up in production at 3am

By the fifth server, I stopped saying "this will be simple." Now I say "this will be simple for the first 80%, and then the universe will test my sanity."

2. Error Handling Is 80% of the Work

The happy path is the easy part. Anyone can write code that works when everything goes right. The real engineering is in what happens when:

• The API returns a 200 with an empty body (yes, this happens)
• The SSL certificate expires mid-connection
• A user passes a string where you expected a number
• The entire internet catches fire (metaphorically)

I learned to wrap every external call in try/catch blocks that log context. Not just "it failed" but "it failed at line 47 when calling endpoint X with parameters Y and the response was Z."

Your future self debugging at 2am will thank you.

3. Documentation Is the Difference Between Adoption and Abandonment

I built two MCP servers with identical functionality. One had a README that said "install and run." The other had examples, common pitfalls, and a troubleshooting section.

Guess which one got used?

People don't read documentation for fun. They read it because they're stuck. If your docs don't solve their immediate problem in 30 seconds, they'll move on.

My README template now includes:

1. One-line description
2. Installation (copy-paste ready)
3. Quick start example (that actually works)
4. Common errors and solutions
5. "If nothing works, check this first" section

4. CI/CD Pipelines Save More Time Than They Cost

I used to think CI/CD was for "real" projects with teams. My little MCP servers didn't need that complexity, right?

Wrong.

The first time I pushed broken code to main at 11pm and had to fix it while half-asleep, I understood. Now every server gets:

• Linting on every PR (catches my stupid mistakes)
• Tests that run automatically (so I don't break things)
• Auto-deploy on merge (so I don't forget)

It took 20 minutes to set up the first time. It saves me 20 minutes on every single deploy.

5. The Best Tools Are The Ones You Actually Use

I built fancy features that nobody asked for. Webhook integrations. GraphQL support. Real-time dashboards.

Know what got used?

The simple CLI that did one thing well.

I learned to build the minimum viable thing first. Get it working. Get people using it. Then add features based on what they actually need, not what I think would be cool.

The Meta-Lesson

After ten servers, I noticed something: the good ones all felt boring to build. No clever hacks. No architectural gymnastics. Just solid, predictable code that handled edge cases gracefully.

The bad ones? They had clever abstractions that made me feel smart when I wrote them and made me cry when I debugged them.

Boring code is good code. Clever code is technical debt wearing a disguise.

I'm still learning this lesson. The difference is now I recognize the warning signs.

When I catch myself thinking "this is elegant," I pause. When I think "this is obvious," I ship it.

The basement has taught me many things. This might be the most important: the best engineering feels like cheating because it's so simple.

But simple is hard. Simple takes discipline. Simple means saying no to all the cool things you could add and yes to the boring thing that actually works.

Ten servers later, I'm still working on it.