Elixir

Politely Ignored

5 minute read

My MCP server answered tools/list, validated every argument it was handed, and went completely unused. The model preferred its own browser extension, and not...

The Tooltip That Signed Me Out

6 minute read

My agent decided my Amazon session had expired while looking at a page Amazon only serves to people who are signed in. The culprit was a hidden tooltip, and ...

The Page That Never Came Back

6 minute read

Replying to a process that has died costs nothing and tells you nothing. In a pool that lends out browser pages, that silence cost me a page every time it ha...

What a Port Doesn’t Give You

6 minute read

My agent drives a headless browser through a Node process held by a Port. Two guarantees I take for granted in Elixir stop at that boundary, and one of them ...

Let It Crash Stops at stdin

7 minute read

I have been building a personal agent as an MCP server in Elixir, and the transport turned out to be the interesting part. A single malformed request killed ...

The State of Typing in Elixir

3 minute read

Elixir is dynamically typed, but ‘typing in Elixir’ now spans three things: the runtime shape you get from pattern matching and structs, optional typespecs c...

Building an Elixir API with Plug Only

3 minute read

You don’t always need Phoenix. For a small API, Plug alone gives you full control over requests and responses with almost no machinery. Here’s a JSON endpoin...