Drift

Test-driven development for AI workflows - define your standards, validate your project, iterate to compliance.

What It Does

Drift validates your AI agent projects against custom rules you define. No built-in opinions - you write the rules in .drift.yaml, Drift validates against them.

Quick Example

1. Create .drift.yaml with your rules:

rule_definitions:
  claude_md_exists:
    description: "Project must have CLAUDE.md"
    scope: project_level
    phases:
      - name: check_file
        type: file_exists
        file_path: CLAUDE.md
        failure_message: "CLAUDE.md is missing"

2. Run validation:

uvx --from ai-drift drift

3. Fix issues, re-run until green.

That's it. Define standards → validate → fix → iterate.

Installation

Run directly with uv (no installation needed):

uvx --from ai-drift drift

Or install with uv:

uv pip install ai-drift

Common Workflow

# 1. Define your standards in .drift.yaml
# 2. Run validation
uvx --from ai-drift drift

# 3. Generate AI prompts to create missing files
uvx --from ai-drift drift draft --target-rule skill_validation > prompt.md

# 4. Fix issues manually or with AI
# 5. Re-validate until green
uvx --from ai-drift drift

What You Can Validate

Define rules to check:

• Required files exist (CLAUDE.md, README.md, etc.)
• Link integrity (no broken file references)
• YAML frontmatter structure
• Dependency health (no redundant transitive dependencies)
• File format compliance (regex patterns)
• Content quality (with optional LLM-based rules)

Examples: See .drift.yaml in this repo.

Configuration Options

Parameter Overrides

Override validator parameters at different levels using parameter override configuration:

# Validator-level overrides - apply to all rules using a validator
validator_param_overrides:
  core:file_exists:
    merge:
      ignore_patterns:
        - ".venv/**"
        - "node_modules/**/*"
        - "**/*.tmp"

  core:markdown_link:
    merge:
      ignore_patterns:
        - "https://example.com/**"
        - "http://localhost:**"

# Rule-level overrides - apply to specific rules
rule_param_overrides:
  Python::documentation:
    merge:
      ignore_patterns:
        - "tests/**"

  # Phase-specific override
  General::skill_validation::check_links:
    replace:
      check_external_urls: false

# Skip entire rules or phases
ignore_validation_rules:
  - "Claude Code::skill_validation::check_description_quality"
  - "Python::formatting"

Override Strategies:

• merge: Extends lists/dicts (for ignore_patterns, etc.)
• replace: Completely replaces parameter value

Pattern Types:

• Glob patterns: *.md, **/*.py, src/**/*
• Regex patterns: Auto-detected by metacharacters (^, $, \(, etc.)
• Literal paths: Exact path matching

Precedence: validator overrides → rule overrides → phase overrides

See Configuration Guide for complete details.

Documentation

• Writing Rules - Define custom validation rules
• Validators Reference - Available validation types
• Draft Command - Generate AI prompts from rules
• CLI Options - Command-line reference
• Configuration - Provider setup and ignore patterns

Development

./test.sh          # Run tests (90%+ coverage required)
./lint.sh          # Run linters
./lint.sh --fix    # Auto-fix formatting

License

MIT