Respect CLAUDE_CONFIG_DIR

[zhubert]

Claude Code supports the environment variable CLAUDE_CONFIG_DIR which specifies where to look for "configuration and data files".

Plural needs to use that appropriate directory if it has been set.

[zhubert]

Implementation Plan: Respect CLAUDE_CONFIG_DIR

Summary

Claude Code supports the CLAUDE_CONFIG_DIR environment variable to override the default ~/.claude directory for configuration and data files. Currently, Plural hardcodes ~/.claude in four separate places. This plan introduces a central helper function and updates all affected callsites.

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Affected Files

File	Location	Current behavior
internal/claudeconfig/mcp.go	discoverMCPToolPatterns()	Reads ~/.claude.json (project MCP config) — not inside ~/.claude/, so likely unaffected
internal/plugins/plugins.go	getClaudeDir()	Returns filepath.Join(home, ".claude")
internal/claude/process_manager.go	credentialsFileExists()	Checks ~/.claude/.credentials.json
internal/claude/process_manager.go	buildContainerRunArgs()	Mounts homeDir + "/.claude" as /home/claude/.claude-host:ro
internal/mcp/server.go	validatePlanPath()	Validates plan path against ~/.claude/plans/

Note on ~/.claude.json: This file lives at $HOME/.claude.json (adjacent to the directory, not inside it). Based on Claude Code's behavior, CLAUDE_CONFIG_DIR only affects the ~/.claude/ directory, not this file. No change needed in internal/claudeconfig/mcp.go.

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Step-by-Step Implementation Plan

Step 1: Add GetClaudeConfigDir() to internal/claudeconfig/

Create a new file internal/claudeconfig/config_dir.go (or add to an existing file) with:

// GetClaudeConfigDir returns the Claude Code configuration directory.
// If the CLAUDE_CONFIG_DIR environment variable is set, it is used as-is.
// Otherwise, falls back to ~/.claude.
func GetClaudeConfigDir() (string, error) {
    if dir := os.Getenv("CLAUDE_CONFIG_DIR"); dir != "" {
        return dir, nil
    }
    home, err := os.UserHomeDir()
    if err != nil {
        return "", err
    }
    return filepath.Join(home, ".claude"), nil
}

This function will have a corresponding test file covering both the env-var path and the fallback path.

Step 2: Update internal/plugins/plugins.go

Replace the private getClaudeDir() function body to call claudeconfig.GetClaudeConfigDir(), or import and use it directly in ListMarketplaces(), ListPlugins().

func getClaudeDir() string {
    dir, err := claudeconfig.GetClaudeConfigDir()
    if err != nil {
        return ""
    }
    return dir
}

Step 3: Update internal/claude/process_manager.go

credentialsFileExists() (line ~1175):

func credentialsFileExists() bool {
    dir, err := claudeconfig.GetClaudeConfigDir()
    if err != nil {
        return false
    }
    _, err = os.Stat(filepath.Join(dir, ".credentials.json"))
    return err == nil
}

buildContainerRunArgs() (line ~1016):

claudeDir, err := claudeconfig.GetClaudeConfigDir()
if err != nil {
    return containerRunResult{}, fmt.Errorf("failed to determine claude config dir: %w", err)
}
// ...
"-v", claudeDir + ":/home/claude/.claude-host:ro",

Step 4: Update internal/mcp/server.go

validatePlanPath() (line ~902):

func validatePlanPath(planPath string) error {
    claudeDir, err := claudeconfig.GetClaudeConfigDir()
    if err != nil {
        return fmt.Errorf("cannot determine claude config directory: %w", err)
    }
    allowedDir := filepath.Join(claudeDir, "plans")
    // ... rest unchanged
}

Step 5: Write tests

• internal/claudeconfig/config_dir_test.go: table-driven tests for GetClaudeConfigDir() covering:
  • CLAUDE_CONFIG_DIR set → returns env var value
  • CLAUDE_CONFIG_DIR unset → returns ~/.claude
  • Both cases with t.Setenv() for isolation
• Update internal/claude/process_manager_test.go to test credentialsFileExists() with CLAUDE_CONFIG_DIR set
• Update internal/mcp/server_test.go plan-path tests to verify CLAUDE_CONFIG_DIR overrides the allowed directory

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Potential Risks / Edge Cases

1. CLAUDE_CONFIG_DIR with trailing slash — filepath.Join normalizes this, so no issue.
2. Relative path in CLAUDE_CONFIG_DIR — Could be surprising. We can document that it's used as-is (matching Claude Code's behavior).
3. Import cycle — internal/claudeconfig is already imported by internal/plugins. Need to verify internal/claude and internal/mcp don't already import claudeconfig in a way that creates a cycle. Quick check shows internal/claude does not currently import claudeconfig, so a new import is needed.
4. Container entrypoint — The entrypoint script in build.go (line 143–152) copies from /home/claude/.claude-host which is the mounted ~/.claude dir. Since Step 3 already mounts the correct directory, no additional change is needed in the Dockerfile template.

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No changes needed

• internal/claudeconfig/mcp.go — reads ~/.claude.json (not inside ~/.claude/), unaffected by CLAUDE_CONFIG_DIR
• internal/container/build.go — Dockerfile template copies from the mount point /home/claude/.claude-host, which is fixed inside the container; the host side is already fixed in Step 3

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Questions / Clarifications

None — the scope is well-defined. Ready to implement once approved.

[zhubert]

The plan above is ready for your review. Reply with your feedback to request changes, or reply with an approval (e.g. "LGTM", "looks good", "approved") to proceed.

[zhubert]

approved

[zhubert]

A pull request is ready for your review: #326

Please review and approve it to proceed.