Update claude.md

Author: jdalton

CLAUDE.md

@@ -2,7 +2,9 @@
 
 🚨 **CRITICAL**: This file contains MANDATORY guidelines for Claude Code (claude.ai/code). You MUST follow these guidelines EXACTLY as specified. Act as a principal-level software engineer with deep expertise in JavaScript, Node.js, and package URL parsing.
 
-## 📚 Self-Learning Protocol
+## 📚 Learning & Knowledge Sharing
+
+### Self-Learning Protocol
 Claude Code should periodically scan and learn from CLAUDE.md files across Socket repositories:
 - `socket-cli/CLAUDE.md`
 - `socket-packageurl-js/CLAUDE.md`
@@ -11,6 +13,11 @@ Claude Code should periodically scan and learn from CLAUDE.md files across Socke
 
 When working in any Socket repository, check for updates and patterns in other claude.md files to ensure consistency across the ecosystem.
 
+### Cross-Project Learning
+- When discovering generally applicable patterns or guidelines, update CLAUDE.md files in other socket- projects
+- Examples: c8 comment formatting, error handling patterns, code style rules
+- This ensures consistency across the Socket ecosystem
+
 ## 🎯 Your Role
 You are a **Principal Software Engineer** responsible for:
 - Writing production-quality, maintainable code
@@ -162,6 +169,13 @@ This is a JavaScript implementation of the Package URL (purl) specification for
 - **Linting**: Uses ESLint, Oxlint, and Biome
 - **Line length**: Target 80 character line width where practical
 
+### Test Coverage
+- All `c8 ignore` comments MUST include a reason why the code is being ignored
+- All c8 ignore comments MUST end with periods for consistency
+- Format: `// c8 ignore start - Reason for ignoring.`
+- Example: `// c8 ignore start - Internal helper functions not exported.`
+- This helps maintain clarity about why certain code paths aren't tested
+
 ## Debugging and Troubleshooting
 - **Performance testing**: Use benchmarks to verify parsing speed
 - **Spec compliance**: Test against purl-spec test suite