Index a codebase to build the dependency graph. Supports Haskell and ReScript. Performs incremental indexing (only changed files) unless force_full is set. For Haskell, optionally uses hie-reader binary for rich type info; falls back to source parsing.

Get indexing status for all codebases or a specific one. Shows file count, symbol count, edge count, last indexed time.

Trace what a function/component depends on (outgoing edges). Shows all functions called, types used, and components rendered. Use this to answer: "What do I need to mock to test function X?" or "What is the full flow from this endpoint to the database?"

Trace what depends on a function/component (incoming edges). Shows all callers, importers, and parent components. Use this to answer: "I changed function X, what tests need updating?" or "What entry points reach this code?"

Trace module-level dependencies (coarser but always available). Shows which files/modules depend on which.

Given changed files or symbols, determine the full impact: what tests might break, what entry points are affected, what downstream consumers exist.

Get detailed information about a specific symbol: definition location, type signature, direct callees, and direct callers.

List all symbols defined in a module/file: functions, types, components, exports.

Search for symbols by name pattern. Supports partial matching and * wildcards. Use when you know a function name but not its full module path.

Get everything needed to write tests for a function or module: the function itself, all its direct dependencies (what to mock), all its callers (usage examples), type definitions it uses, and file paths for all involved code.