2025: The Year in LLMs
Simon Willison's Weblog
This is the third in my annual series reviewing everything that happened in the LLM space over the past 12 months. For previous years see Stuff we figured out about AI in 2023 and Things we learned about LLMs in 2024.
Highlights & Annotations
But if you define agents as LLM systems that can perform useful work via tool calls over multiple steps then agents are here and they are proving to be extraordinarily useful.
Ref. D858-A
The Deep Research pattern—where you challenge an LLM to gather information and it churns away for 15+ minutes building you a detailed report—was popular in the first half of the year but has fallen out of fashion now that GPT-5 Thinking (and Google’s “AI mode”, a significantly better product than their terrible “AI overviews”) can produce comparable results in a fraction of the time. I consider this to be an agent pattern, and one that works really well.
Ref. 4EE0-B
Johann describes the “Normalization of Deviance” phenomenon, where repeated exposure to risky behaviour without negative consequences leads people and organizations to accept that risky behaviour as normal.
Ref. 4053-C