Simon Willison’s Weblog


Wednesday, 6th December 2023

Long context prompting for Claude 2.1. Claude 2.1 has a 200,000 token context, enough for around 500 pages of text. Convincing it to answer a question based on a single sentence buried deep within that content can be difficult, but Anthropic found that adding “Assistant: Here is the most relevant sentence in the context:” to the end of the prompt was enough to raise Claude 2.1’s score from 27% to 98% on their evaluation. # 11:44 pm

Ice Cubes GPT-4 prompts. The Ice Cubes open source Mastodon app recently grew a very good “describe this image” feature to help people add alt text to their images. I had a dig around in their repo and it turns out they’re using GPT-4 Vision for this (and regular GPT-4 for other features), passing the image with this prompt:

“What’s in this image? Be brief, it’s for image alt description on a social network. Don’t write in the first person.” # 7:38 pm

2023 » December