What the Evaluations Can—and Cannot—Tell Us
Magentic-One’s reported scores are useful only when read together with the conditions that produced them. This chapter focuses on that connection: how AutoGenBench controls stateful environments, what the benchmark results measure, and how ablations and failure analysis reveal the contributions and weaknesses behind a headline percentage. The reader will be able to report the main findings without turning them into an absolute ranking, and to distinguish evidence about orchestration from evidence about capability coverage or production reliability.
An evaluation is a controlled environment, not just a score
Agentic systems act on stateful environments, so the order and conditions of an experiment can change the result. If the first system installs a library, later systems may inherit it. If an agent deletes a file or leaves an environment in a broken state, subsequent tasks may be harmed. An apparently higher score can therefore reflect a cleaner starting state or a side effect left by an earlier run rather than a better workflow.
AutoGenBench was introduced to address this problem. It starts tasks in freshly initialized Docker containers, keeps the task logs in a central location, and supports repeated runs and parallel execution. Fresh containers reduce cross-run contamination. Repetition exposes variance from stochastic language-model calls. Central logs make the trace available for analysis, while isolation limits the consequences of an agent’s actions. These are not peripheral conveniences: they define what it means for two agent systems to face comparable conditions.
The diagram captures an evidence chain. A configuration is tested on a benchmark under a protocol; the run produces metrics, ablations, and observed errors; those outputs support claims with a defined scope. A score detached from the configuration or protocol is not a complete finding. Nor is an error label by itself a causal explanation. The relationship among them is what allows an evaluator to ask what changed and what that change can reasonably establish.
Magentic-One was evaluated on three demanding benchmarks. GAIA contains multimodal, real-world question-and-answer tasks that require several tools and steps. AssistantBench contains realistic, time-consuming questions involving web navigation and multi-step reasoning. WebArena places agents in functional synthetic websites and evaluates both answers and desired website states. These benchmarks differ in their task distributions and verification arrangements, so a percentage from one cannot be treated as directly interchangeable with a percentage from another.
The paper reports the results for two model configurations. With GPT-4o used across the team, Magentic-One achieved a 32.33% exact task-completion rate on the GAIA test set, 11.0% exact match and 25.3% softer accuracy on AssistantBench, and 32.8% on WebArena. With GPT-4o and o1-preview combined for selected roles, the reported rates were 38.0% on GAIA, 13.3% exact match and 27.7% softer accuracy on AssistantBench.