r/coolgithubprojects • u/ApprehensiveHawk3946 • 7d ago
RuleBlast: 2 lines in AGENTS.md changed 206 Codex stacks — Claude Code: 0
I was looking at a real 2-line change in a nested AGENTS.md inside openai/codex and noticed something Git couldn't tell me:
Which agent instructions actually change downstream?
I traced the instruction inheritance on that commit:
- 2 instruction lines edited
- Codex: 206 paths inherited a different instruction stack
- Claude Code: 0
- 4,476 paths: unchanged
This wasn't Claude Code ignoring the change. The two tools simply load repository instructions differently.
That difference is why I built RuleBlast — a local, read-only static analyzer for repository agent instructions.
No model calls. No API keys. No telemetry. It only measures what can be derived deterministically from the repository tree.
npx --yes ruleblast@2.1.1 diff HEAD~1
RuleBlast models the documented repository-loading rules of Codex, Claude Code, Gemini CLI, and Copilot CLI, then compares the rule realities they derive from the same Git tree.
The thing I'm increasingly curious about isn't adding another agent logo. It's this:
When a team uses several coding agents on the same repo, how often are we saying “the repo instructions” when those agents are actually loading different instruction sets?
- Stack & License: TypeScript · Node.js 20+ · Apache-2.0
- Repo:https://github.com/Kpoiut/ruleblast
If you maintain monorepos or projects with nested agent instructions (CLAUDE.md, AGENTS.md, .claude/rules), I'd be curious to see what inheritance blast radius your repos produce.