# Rulefiles

> A weekly digest of dated, sourced changes in Cursor, Claude Code, Codex and GitHub Copilot, plus a matrix of which agent reads which instruction file.

Every digest item and matrix cell links to an official source and carries a date. Cells marked "unverified" were not confirmed on the cited page, and cells marked "migration only" are mentioned there only as input to a migration command. Pages are plain HTML without cookies or scripts that load data.

## Data

- [Instruction file matrix](https://rulefiles.dev/matrix/): which of 4 tools reads which of 9 instruction files, last reviewed 2026-10-16
- [matrix.json](https://rulefiles.dev/data/matrix.json): the same matrix as JSON
- [digests.json](https://rulefiles.dev/data/digests.json): all digest issues as JSON
- [llms-full.txt](https://rulefiles.dev/llms-full.txt): matrix and digests as one Markdown file
- [License](https://creativecommons.org/licenses/by/4.0/): the data and the text are CC BY 4.0, credit "Rulefiles contributors" and link https://rulefiles.dev/; quoted excerpts belong to their authors; the code is MIT

## Digest

- [Digest for 12 to 18 October 2026 (through 15 October)](https://rulefiles.dev/digest/2026-W42/): 6 dated items, checked 2026-10-15
- [Digest for 5 to 11 October 2026](https://rulefiles.dev/digest/2026-W41/): 11 dated items, checked 2026-10-15
- [Atom feed](https://rulefiles.dev/digest/feed.xml): every issue

## Tools

- [Instruction file generator](https://rulefiles.dev/generator/): builds AGENTS.md, CLAUDE.md, Cursor rules and Copilot instructions in the browser

## Optional

- [About](https://rulefiles.dev/about/): method and limits
- [Privacy](https://rulefiles.dev/privacy/): no cookies, no analytics
- [Sponsors](https://rulefiles.dev/sponsors/): sponsorship policy
- [Legal notice](https://rulefiles.dev/legal/): publisher, host and contact