Hack — 18 Operations for AI Agents

Hack runs some of the largest PHP-descended codebases on earth, with gradual types layered onto web-scale code. act101 navigates classes, functions, and types structurally, so agents move through Hack code at the scale it was built for.

This page is the canonical reference an AI coding agent uses to refactor, query, and analyze Hack code through the act MCP server. 18 operations available: 0 refactor, 18 query, 0 analysis. Each operation is callable from Claude Code, Cursor, Codex, OpenCode, or any MCP-compatible agent host. Click any operation for a stable anchor link suitable for citation.

Query

18 query tools, the same on every supported language. Descriptions live in the shared reference: /docs/query-tools.

callers control_flow data_flow definition diagnostics effect_closure effect_summary fix_auto get_type graph import_organize interface mutations references repo_outline skeleton symbols symbols_batch