Which coding agents read CLAUDE.md?
Claude Code project instructions file.
A cell reads "unverified" when the page we checked does not mention the file. We then have no source, which says nothing about whether the tool reads it. A cell reads "migration only" when the page mentions the file only as input to a migration command such as /init.
- Reads 3
- Only if configured 1
| Tool | Status | Note | Official source | Checked |
|---|---|---|---|---|
| Cursor | Reads |
The help page says: "Cursor reads |
||
| Claude Code | Reads |
Reads ./CLAUDE.md or ./.claude/CLAUDE.md, plus user, managed and local (CLAUDE.local.md) scopes. |
||
| Codex | Only if configured |
Not part of default discovery. The page says Codex also reads names listed in project_doc_fallback_filenames and ignores names not on that list. |
||
| GitHub CopilotRepository custom instructions on GitHub.com (cloud agent, code review) | Reads |
Alternative to AGENTS.md: a single CLAUDE.md in the repository root. |
Data
These rows come from the instruction file matrix, also published as matrix.json. Cells marked unverified are listed on one page.
Other instruction files
AGENTS.mdAGENTS.override.mdGEMINI.md.cursorrules.cursor/rules/ *.mdc .claude/rules/ *.md .github/copilot-instructions.md .github/instructions/ *.instructions.md
How to cite
The data and the text are under CC BY 4.0. Credit the project, link the license, and say what you changed. A cell is a dated reading of an official page, so give the date of the cell, which is shown on it, or the date the matrix was last reviewed.
Suggested credit: "Rulefiles data by Rulefiles contributors, https://rulefiles-preview.pages.dev/matrix/, last reviewed 2026-10-16, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)."
Quoted excerpts of the sources belong to their authors. Link the official page of the cell when you rely on it.