# How Prompt Tuning Improved GPT-5.5 in VS Code

DevFeed: [How Prompt Tuning Improved GPT-5.5 in VS Code](<https://devfeed.tech/articles/how-prompt-tuning-improved-gpt-5-5-in-vs-code-4062.md>)

Original publisher: [Read original article](<https://code.visualstudio.com/blogs/2026/07/06/optimizing-vscode-coding-harness-model-providers>)

Author: VS Code Team

Published: 2026-07-06T00:00:00Z

Content type: article

Language: en

Sources: [Visual Studio Code - Code Editing. Redefined.](<https://devfeed.tech/sources/visual-studio-code-code-editing-redefined.md>)

Topics: [AI Chat](<https://devfeed.tech/topics/ai-chat.md>), [AI Bots](<https://devfeed.tech/topics/ai-bots.md>)

Tags: [agent](<https://devfeed.tech/tags/agent.md>), [blog](<https://devfeed.tech/tags/blog.md>), [coding](<https://devfeed.tech/tags/coding.md>), [experiment](<https://devfeed.tech/tags/experiment.md>), [gpt](<https://devfeed.tech/tags/gpt.md>), [openai](<https://devfeed.tech/tags/openai.md>), [testing](<https://devfeed.tech/tags/testing.md>), [tools](<https://devfeed.tech/tags/tools.md>), [validation](<https://devfeed.tech/tags/validation.md>), [vs-code](<https://devfeed.tech/tags/vs-code.md>)

## AI overview

VS Code and OpenAI tested two system-prompt variants for GPT-5.5 coding agents to reduce exploration and validate edits sooner. The experiment compared the variants with a control on live traffic and shipped the stronger result.

## Source excerpt

See how VS Code and OpenAI tested GPT-5.5 system prompt changes in a two-week experiment, cutting tool calls and tail-end token usage while speeding up edits. Read the full article