model-evaluation

Claude Fable: What Real-World Coding Actually Costs

Claude Fable is Anthropic's newer coding model, and one shipped open-source release gives us a rare concrete number: about $149.25. Here's what Claude Fable is, how to get access, and what a real project costs — every figure attributed to its source.

07/08/2026 · Model Evaluation · 6 min read

Claude Sonnet 5 for Coding Agents: Is the Higher Cost-Per-Task Worth It?

Claude Sonnet 5 keeps Sonnet 4.6's sticker price but a new tokenizer inflates real cost-per-task by roughly 30%. Here's what that means for agentic and coding workloads — and when it's still worth it.

07/02/2026 · Model Evaluation · 7 min read

Can You Trust an AI Model Leaderboard? How LMArena and LLM Benchmarks Really Work

An AI model leaderboard like LMArena is now the industry scoreboard — and a $100M business. Here is how Elo-style ranking actually works, where it misleads, and how to evaluate models for your own use case.

06/30/2026 · Model Evaluation · 8 min read

How to Evaluate AI Agents: A Practical Reliability Playbook

AI agent evaluation is the discipline most teams skip — and the one that decides whether your agent survives production. Here's how to test agents for correctness, reliability, memory, and failure modes before and after you ship.

06/29/2026 · Model Evaluation · 9 min read

How to Benchmark AI Agents on Your Own Tools (Not Just Leaderboards)

Public leaderboards won't tell you if a model can actually drive your tools. Here's how to build a lightweight, reproducible agentic eval against your own harness — and why local models are now in the running.

06/28/2026 · Model Evaluation · 9 min read

Research Agent Data Leakage: Inside the MosaicLeaks Benchmark

Research agent data leakage is a measurable failure mode, not a hypothetical. ServiceNow's MosaicLeaks benchmark shows how deep research agents leak private context through their search queries — and why you can't prompt the problem away.

06/20/2026 · Model Evaluation · 10 min read

GLM-5.2 Benchmarks: Is This the Best Open-Weights Agent Model of 2026?

GLM-5.2's benchmarks put a 753B open-weights model within a point of frontier labs on long-horizon agent work — but running it locally is another story. Here's what the numbers actually say.

06/19/2026 · Model Evaluation · 9 min read