Templates & Utility Packages
These packages support applications around the agent loop. They are intentionally small and do not define a separate application framework.
Prompt Templates
prompt.New renders double-brace placeholders. WithDefaults supplies fallback values and WithStrict rejects missing variables. RenderMessages wraps rendered content as a system message. Non-strict rendering leaves missing placeholders unchanged.
template := prompt.New("You review {{language}} code for {{project}}.").
WithDefaults(map[string]string{"language": "Go"}).
WithStrict()
text, err := template.Render(map[string]string{"project": "Covonaut"})
if err != nil {
return err
}Template rendering is textual substitution, not escaping, input sanitization, or authorization. Keep untrusted content out of privileged instruction slots where possible. The simple Format helper does not provide strict missing-value validation.
File Mutation Queue
filequeue.New creates a process-local queue that serializes operations on a resolved file path. WithFile wraps a mutation; WithFileResult returns a value. ReadFileSafe and WriteFileSafe use the same queue.
Path resolution accounts for existing symlinks where possible, and unused lock entries are released. This is not a distributed lock, an atomic multi-file transaction, or protection against a process that does not use the queue. Resolve permissions and allowed roots separately, and use one shared queue where participating operations must serialize.
Fuzzy Text
fuzzy.Find attempts exact matching before normalized matching. Normalization handles selected punctuation, space, and line-ending differences. Replace replaces the first matching occurrence; LevenshteinDistance is a separate distance helper.
Use these helpers for controlled edit workflows, not arbitrary semantic code transformation. Check which occurrence is being changed and inspect a diff; similar-looking text is not proof that a patch targets the intended code.
Environment Helpers
pkg/util includes ErrorString, DefaultString, FirstNonEmpty, and EnvOrDefault. These helpers simplify application configuration but do not validate credentials, model names, or URLs. Validate required values before starting services.