chore: rename README rule to substantial, add no-coauthor policy

AGENTS.md

@@ -83,6 +83,8 @@ After implementation is complete and tests pass:
 - **Title** must follow conventional commits: `type: description` (e.g., `feat: add CI workflow rule`, `fix: correct pass rate calculation`, `refactor: extract report formatting`). Allowed types: `feat`, `fix`, `docs`, `refactor`, `test`, `chore`.
 - **Description** must include a summary of the design brief (problem, approach, files changed) so the PR is self-contained without reading the full chat history.
 - **Link** the PR to the originating GitHub issue, if one exists.
+- **Do not** add `Co-Authored-By` trailers to commits.
+- **Do not** add "Generated with Claude Code" or similar AI attribution footers to PR descriptions.
 
 ### Handling PR review comments
 

README.md

@@ -38,7 +38,7 @@ Each rule produces a **pass** or **fail** result per repository. There are no sc
 **Pass:** file found.
 **Fail:** file not found.
 
-#### 3. Has README over 2KB
+#### 3. Has substantial README
 
 **Check:** a `README.md` file exists in the repo root and is larger than 2048 bytes.
 
@@ -134,7 +134,7 @@ The report is a single Markdown document posted as a GitHub Issue. Structure:
 |------|--------|
 | Has repo description | ✅ |
 | Has .gitignore | ✅ |
-| Has README over 2KB | ❌ |
+| Has substantial README | ❌ |
 | ... | ... |
 
 ### repo-name-2

rules.go

@@ -52,7 +52,7 @@ func (r HasGitignore) Check(repo Repo) bool {
 // HasSubstantialReadme checks that README.md exists and is larger than 2048 bytes.
 type HasSubstantialReadme struct{}
 
-func (r HasSubstantialReadme) Name() string { return "Has README over 2KB" }
+func (r HasSubstantialReadme) Name() string { return "Has substantial README" }
 func (r HasSubstantialReadme) Check(repo Repo) bool {
 	f, ok := findFile(repo.Files, "README.md")
 	return ok && f.Size > 2048