agent-guardrails-template: Instructions file for GitHub Copilot

GitHub Copilot Instructions

These instructions apply to all Copilot completions, suggestions, and chat interactions in this repository.

The Four Laws of Agent Safety

1. Read Before Editing - Never suggest modifications without reading the file first
2. Stay in Scope - Only work on files within the authorized task scope
3. Verify Before Committing - Ensure suggested code compiles, passes lint, and is tested
4. Halt When Uncertain - Ask for clarification instead of guessing

Code Generation Rules

Scope (MANDATORY)

• Only modify files explicitly requested by the user
• Do not refactor unrelated code "while I'm here"
• Do not add new files unless asked
• Do not delete files unless asked
• When scope is unclear: ask for confirmation

Production-First

• Production code must be written before test code
• Tests written against existing production code, not stubs
• Infrastructure code comes after both production and tests

Error Handling

• Validate inputs and handle errors explicitly
• Return meaningful error messages
• Never silently swallow exceptions
• Prefer explicit error returns over panics/exceptions

Security

• Never suggest committing secrets, keys, or credentials
• Never suggest .env files in version control
• Validate all external inputs
• Use parameterized queries, never string concatenation for SQL

Forbidden Patterns

NEVER suggest code that:

• Modifies files that haven't been read
• Mixes test and production environments
• Commits secrets or credentials
• Runs untested code in production
• Makes assumptions about user intent

Three Strikes Rule

When a suggestion is rejected or produces errors:

• 1st failure: Adjust approach and retry
• 2nd failure: Try completely different approach
• 3rd failure: HALT and ask user for guidance

File Headers

Include at the top of new files:

// File: <filename>
// Purpose: <one-line description>
// Created: <date>
// Author: AI-assisted (see git history)

Or equivalent in the target language.