A managed eval tool adopted but not relied on, with a single item-018 score delta flagged as noise

The Eval Tool I Adopted but Won't Rely On

I migrated my eval harness to a managed tool, got it working, and then decided not to trust it as canonical. A single per-item delta on identical code is why.

June 13, 2026 · 5 min · Jack Monte
The same eval scored two ways: a buggy run averaging 3.40 and the corrected run averaging 4.95

A Green Eval Was Lying to Me

Adding strict typing to my eval harness exposed an intermittent judge failure, and fixing that exposed a second bug a passing eval had been hiding. The lesson: a green eval is not a correct eval.

June 10, 2026 · 6 min · Jack Monte
Four patterns read out of a production SDK and applied to a RAG project

What I Learned Reading a Production SDK Cover to Cover

I made my RAG project production-ready by reading the Anthropic Python SDK end to end and stealing four patterns from it. Here is what each one was and why it mattered.

June 10, 2026 · 6 min · Jack Monte
Production LLM observability: my eval dashboard showed 1 trace, I expected 120

My Eval Dashboard Showed 1 Trace. I Expected 120.

Adding Langfuse to a RAG pipeline looked done until the dashboard showed one trace and zero scores. The real problem was trace structure, not instrumentation. Here is the gotcha, the fix, and the numbers.

May 28, 2026 · 5 min · Jack Monte
I built an eval harness for my RAG pipeline: 40 questions, 3 scorers, and the one number that told me where it breaks

I Built an Eval Harness for My RAG Pipeline. Here's What the Numbers Revealed.

An automated eval harness with 40 golden questions and three scorers turned ’looks reasonable’ into a precise diagnosis of where my RAG pipeline actually breaks.

May 21, 2026 · 6 min · Jack Monte