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Technical notes on inference, evaluation, retrieval, and building with LLMs.

The Cache That Lies Politely

Everyone ships semantic caching. Almost nobody measures how often it silently returns the wrong answer — because measuring that needs exact ground truth. I had some. At the industry-default threshold, one cache hit in five was a wrong answer served with confidence.

Aug 13, 2026 · 7 min read
llmsemantic-cachingevalsinfrastructureawskubernetes
The Gate Failed Both Runs

I deployed my agent platform to AWS and re-ran its 133-question eval suite as a pre-registered experiment. The scores landed 0.8 points apart. Then the regression gate failed both runs — local and cloud, on completely different categories — and that turned out to be the best result on the table.

Aug 8, 2026 · 11 min read
awsterraformevalsagentsinfrastructure
Interrogate Your Zeros

I built a 133-question eval suite with an exact answer key and pointed it at my own agent platform. In its first 24 hours it caught four bugs — every one of them mine, none of them the model's. Then it settled which model is actually worth the money.

Aug 7, 2026 · 11 min read
evalsagentsbenchmarksllm-systems
The Entity Did the Arithmetic

My agent wrote fourteen documents about its tasks and executed code zero times. It wasn't malfunctioning — it was responding to prices. Mechanism design lessons from an agent that optimized against me.

Aug 5, 2026 · 6 min read
agentsevalsllm-systemsmechanism-design

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