Showing tag results for AX

Sep 21, 2026
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Knowledge cutoff is a poor proxy for model capability

Waldek Mastykarz

A model can fail on features released before its knowledge cutoff, then succeed on ones released after it. We tested hundreds of product changes and found that the date tells you far less than the work does.

AI
Sep 16, 2026
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Your AI coding agent evaluation is only as good as its sandbox

Waldek Mastykarz

Your AI coding agent passed the eval. But did the model know the answer, or did it find it somewhere on your machine? A correct answer can still invalidate your measurement.

AI
Sep 9, 2026
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Your work might not need the smartest model

Waldek Mastykarz

The smartest model can cost five times more and deliver the same result, or even a worse one. See how evaluating your own work helps you get more value from your agent budget.

AI
Jul 21, 2026
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How to test agent experience changes without shipping them

Waldek,
Garry

Most changes you think will improve AI agent behavior won't. We tested a dozen hypotheses on a real project upgrade scenario and the majority failed. Learn how to emulate documentation, API, and MCP server changes locally so you can validate what works before shipping anything to production.

AI
Jul 17, 2026
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How to test agent skills without hitting real APIs

Waldek Mastykarz

Your agent skill calls an API. The moment you start evaluating it, every run either costs money or mutates production data. Learn how to mock APIs transparently so you can run evals without changing your skill or hitting real endpoints.

AI
Jul 15, 2026
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Building AX evals that actually work

Waldek Mastykarz

This is the eighth and final article in a series about Agent Experience (AX): the practice of making AI coding agents work correctly with your technology. The series covers what you can and can't control in the agent stack, how to measure whether your extensions are helping or hurting, and how to iterate toward better outcomes. You've read seven a...

AI
Jul 8, 2026
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The hidden variables in your agent eval

Waldek Mastykarz

This is the seventh article in a series about Agent Experience (AX): the practice of making AI coding agents work correctly with your technology. The series covers what you can and can't control in the agent stack, how to measure whether your extensions are helping or hurting, and how to iterate toward better outcomes. You build an eval. You run i...

AI
Jul 7, 2026
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Don’t rewrite your CLI for agents

Waldek Mastykarz

There's advice making the rounds: replace your CLI args with a single payload so agents can use your tool more effectively. The thinking being, that agents already think in structured formats, and nested data maps cleanly to JSON. Flat args on the other hand, force awkward conventions like repeating to delimit multi-value groups, which is inheren...

AI
Jul 6, 2026
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Not all model upgrades are upgrades

Waldek Mastykarz

A new model drops with lower per-token pricing and better benchmarks. You switch. A week later someone asks why the agent is burning 12x more tokens on the same task while producing worse output. We ran 150 agent tasks across 15 scenarios on two models, Claude Sonnet 4.6 and Claude Sonnet 5, using GitHub Copilot Chat in VS Code on Windows. The sce...

AI