Support hidden config files (e.g. .claude/CLAUDE.md or .CLAUDE.md) for project-level instruction

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When using CLAUDE.md or CLAUDE.local.md for project-level instructions, the files are always visible in the project root directory. For users who want to keep their workspace clean and don't want these config files cluttering the file listing, there is no hidden file option. The only way to avoid visible files is using the global
~/.claude/CLAUDE.md, which cannot provide project-specific instructions.

Proposed Solution

Support hidden config file locations at the project level, for example:

• .claude/CLAUDE.md (hidden directory, similar to .git/, .vscode/)
• .CLAUDE.md (hidden file with dot prefix)

Claude Code would look for instructions in these locations in addition to the existing CLAUDE.md and CLAUDE.local.md. Priority order could be: CLAUDE.md > .CLAUDE.md > .claude/CLAUDE.md (or merged).

Alternative Solutions

Currently I work around this by using the global ~/.claude/CLAUDE.md for personal preferences, but this doesn't support project-specific instructions without a visible file. Adding CLAUDE.local.md to .gitignore avoids git tracking but the file is still visible in the directory listing and IDE file explorer.

Priority

High - Significant impact on productivity

Feature Category

File operations

Use Case Example

1. I have a monorepo workspace directory with multiple projects
2. I want project-specific Claude Code instructions without adding visible files to the root
3. With this feature, I could place instructions in .claude/CLAUDE.md — the dotfile convention keeps the workspace root clean, consistent with how .git/, .vscode/, .idea/ work
4. This is especially useful when the project root already has many config files and I want to reduce clutter

Additional Context

The dotfile/dot-directory convention is well-established in the ecosystem (.git, .vscode, .eslintrc, .prettierrc, etc.). Supporting .claude/ as a hidden config directory would feel natural to most developers and align with existing tooling patterns.