Teach Claude to handle user-pasted error messages efficiently

When the user pastes a specific error (stack trace, build failure,
"failed to execute X"), Claude now follows the error directly to the
relevant files instead of exploring the whole codebase.

https://claude.ai/code/session_01Fzv8baXnEVVhnrffAb3Ucc

CLAUDE.md

@@ -4,9 +4,26 @@ This file is read automatically by Claude Code at the start of every session.
 It teaches Claude to work efficiently on large codebases and avoid running out
 of usage mid-task.
 
-## Finding Errors in Large Codebases
+## When the User Pastes an Error Message
 
-When asked to find or fix errors, bugs, or issues across the codebase:
+The user often arrives with a specific error they hit — a build failure, a
+runtime crash, a stack trace, a "failed to execute X" message. When this happens:
+
+1. **Read the error carefully.** The file names, line numbers, and error type
+   are already in the message. Don't go searching the whole codebase.
+2. **Go directly to the file(s) mentioned in the error.** Read only those files,
+   and only the relevant sections (the function or area around the line number).
+3. **Trace the cause.** If the error references an import, a missing variable,
+   or a function call, grep for that specific symbol — don't read surrounding
+   files "for context."
+4. **Fix it, verify, commit.** After fixing, run the project's build/test
+   command (see Project-Specific Commands below) to confirm the fix works.
+
+The key rule: **the error message IS your roadmap. Follow it, don't explore.**
+
+## Finding Errors Across the Codebase
+
+When asked to find or fix errors broadly (not a specific error message):
 
 1. **Run the scanner first.** Execute: `python scan.py`
    This runs the project's linters, tests, and type checkers in seconds.