mvanhorn/last30days-skill · error

engine: clean tmp cache: %w

Error message

engine: clean tmp cache: %w

What it means

Error "engine: clean tmp cache: %w" thrown in mvanhorn/last30days-skill.

Source

Thrown at mcp/internal/engine/extract.go:77

// use Ensure with an explicit temp dir.
func EnsureUserCache(src fs.FS, version string) (string, error) {
	if override := os.Getenv(CacheEnvOverride); override != "" {
		return Ensure(src, override, version)
	}
	base, err := os.UserCacheDir()
	if err != nil {
		return "", fmt.Errorf("engine: resolve user cache dir (set %s to override): %w", CacheEnvOverride, err)
	}
	return Ensure(src, base, version)
}

func ensureLocked(src fs.FS, cacheDir, version string) error {
	if sentinelMatches(cacheDir, version) {
		return nil
	}
	tmpDir := cacheDir + ".tmp"
	if err := os.RemoveAll(tmpDir); err != nil {
		return fmt.Errorf("engine: clean tmp cache: %w", err)
	}
	if err := os.MkdirAll(tmpDir, 0o755); err != nil {
		return fmt.Errorf("engine: create tmp cache (%s, set %s to override): %w", tmpDir, CacheEnvOverride, err)
	}
	if err := extractAll(src, tmpDir); err != nil {
		_ = os.RemoveAll(tmpDir)
		return err
	}
	sentinel := filepath.Join(tmpDir, SentinelFilename)
	if err := os.WriteFile(sentinel, []byte(version), 0o644); err != nil {
		_ = os.RemoveAll(tmpDir)
		return fmt.Errorf("engine: write sentinel: %w", err)
	}
	if err := os.RemoveAll(cacheDir); err != nil {
		_ = os.RemoveAll(tmpDir)
		return fmt.Errorf("engine: clean old cache: %w", err)
	}
	if err := os.Rename(tmpDir, cacheDir); err != nil {

View on GitHub (pinned to c7460f6114)

Solutions

1. Remove the stale .tmp cache directory manually and retry.
2. Check permissions on the cache directory and ensure no other process holds files open inside it.

When it happens

Trigger: Fires when the engine fails to remove a stale temporary cache directory before extraction, usually due to permission problems or files still held open by another process.

Common situations: See trigger scenarios.

AI-assisted analysis of mvanhorn/last30days-skill@c7460f6114 (2026-08-15). Data as JSON: /api/errors/1352ff295dcd96af. Report an issue: GitHub.