Key Points

Anthropic has published Claude system prompts and provided them as Markdown, enabling their historical changes to be analyzed more systematically.
The article explains a Git-based exploration approach that breaks a monolithic prompt document into granular files grouped by model and model family, then adds timestamped commit history.
Researchers can use standard Git tools like `git log`, `diff`, and `blame` to trace how system prompts evolve over time and attribute specific changes to dates without manual parsing.
The author used the technique to write detailed notes comparing changes between Claude Opus 4.6 and Opus 4.7 system prompts.
The post positions this workflow as a practical research aid for understanding model behavior shifts caused by prompt revisions.

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18th April 2026

Research Claude system prompts as a git timeline — Anthropic's published system prompt history for Claude is transformed into a git-based exploration tool, breaking up the monolithic markdown source into granular files and timestamped commits. By structuring extracted prompts per model, family, and revision, researchers can leverage `git log`, `diff`, and `blame` to trace prompt evolution, compare differences, and attribute changes to specific dates—all without manual parsing.

Anthropic publish the system prompts for Claude chat and make that page available as Markdown. I had Claude Code turn that page into separate files for each model and model family with fake git commit dates to enable browsing the changes via the GitHub commit view.

I used this to write my own detailed notes on the changes between Opus 4.6 and 4.7.

Posted 18th April 2026 at 12:25 pm