Post by Simon Willison on X

Simon Willison@simonw

Here's my enormous round-up of everything we learned about LLMs in 2025 - the third in my annual series of reviews of the past twelve months t.co This year it's divided into 26 sections! This is the table of contents:

The year of “reasoning”
The year of agents
The year of coding agents and Claude Code
The year of LLMs on the command-line
The year of YOLO and the Normalization of Deviance
The year of $200/month subscriptions
The year of top-ranked Chinese open weight models
The year of long tasks
The year of prompt-driven image editing
The year models won gold in academic competitions
The year that Llama lost its way
The year that OpenAI lost their lead
The year of Gemini
The year of pelicans riding bicycles
The year I built 110 tools
The year of the snitch!
The year of vibe coding
The (only?) year of MCP
The year of alarmingly AI-enabled browsers
The year of the lethal trifecta
The year of programming on my phone
The year of conformance suites
The year local models got good, but cloud models got even better
The year of slop
The year that data centers got extremely unpopular
My own words of the year

4.9K likes101 repliesPosted Dec 31, 2025

View the original on X Written by Simon Willison. Captured Sep 4, 2026.

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