Filter blocked entries from list_directory tool output

[Copilot]

execListDirectory validated the requested path but then shelled out to ls -la/Get-ChildItem, which exposed blocked filenames (.env, .ssh/, *.key, etc.) in the output even when the directory itself was allowed.

Changes

• internal/tools/tools.go: Replace shell-out with os.ReadDir + per-entry isBlocked filter. Entries whose relative path cannot be computed are skipped as a fail-safe (avoid accidentally surfacing a file we can't verify).

for _, entry := range entries {
    rel, relErr := filepath.Rel(cwd, filepath.Join(absPath, entry.Name()))
    if relErr != nil || isBlocked(rel) {
        continue  // skip unverifiable or blocked entries
    }
    // format and append entry
}

• internal/tools/tools_additional_test.go: Replace the ls-stub failure test with a non-existent directory test; add TestExecListDirectory_BlockedEntriesFiltered to assert .env is absent and safe.txt is present in listing output.

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[Copilot]

Pull request overview

This PR updates the list_directory tool implementation to avoid leaking blocked/sensitive filenames (e.g., .env, .ssh, *.key) in directory listings by switching from shelling out to native directory reads and applying per-entry filtering.

Changes:

• Replaced execListDirectory shell-out (ls -la / PowerShell) with os.ReadDir and per-entry isBlocked filtering.
• Updated tests to remove command-stub failure coverage and add coverage asserting blocked entries are filtered from tool output.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
internal/tools/tools.go	Implements os.ReadDir-based listing and filters out blocked entries before formatting output.
internal/tools/tools_additional_test.go	Adds a blocked-entry filtering test and replaces the prior shell-command failure test with a non-existent directory case.

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[Copilot]

The permission/type string is being built as entryType + info.Mode().Perm().String(). Perm().String() already includes a leading type character (typically -), so this will produce malformed strings like --rw-r--r-- / d-rwx.... Consider using info.Mode().String() directly, or strip the leading char from the perm string before prefixing with entryType so the output format is consistent.

Suggested change

	fmt.Fprintf(&b, "%s %10d %s %s\n", entryType+info.Mode().Perm().String(), size, info.ModTime().Format("Jan _2 15:04"), entry.Name())
	permStr := info.Mode().Perm().String()
	if len(permStr) > 0 {
	permStr = permStr[1:]
	}
	fmt.Fprintf(&b, "%s %10d %s %s\n", entryType+permStr, size, info.ModTime().Format("Jan _2 15:04"), entry.Name())

[Copilot]

entry.Info() failures are currently silently skipped with a comment implying the entry was removed. In practice Info() can also fail due to permission errors or filesystem issues, and skipping will make the listing incomplete without surfacing why. Consider either (a) returning an error when Info() fails for reasons other than os.IsNotExist, or (b) still emitting the entry with placeholder size/time/mode so users can see it exists.

Suggested change

	// Entry may have been removed after ReadDir; skip it.
	continue
	if os.IsNotExist(infoErr) {
	// Entry may have been removed after ReadDir; skip it.
	continue
	}
	return "", fmt.Errorf("list_directory failed to stat %q: %w", entry.Name(), infoErr)

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Accept regular-file paths in list_directory

Calling os.ReadDir(absPath) unconditionally now makes list_directory fail with not a directory whenever the provided path is a regular file, even though path validation allows file paths and the previous implementation returned a listing for them via ls -la/Get-ChildItem. This is a behavior regression that surfaces to users when they pass a file path (e.g., README.md) and now get a hard error instead of metadata output.

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