Code Navigation

Decision Tree: Serena vs Native Tools

Serena Capabilities

Symbol Navigation

• find_symbol: Locate symbol definitions across the codebase
• get_symbols_overview: Get file structure without reading full content (50-75% token savings)

Impact Analysis

• find_referencing_symbols: Find all callers/users of any symbol across the codebase

Precise Edits

• replace_symbol_body: Replace entire function/method bodies
• insert_before_symbol: Insert code before a symbol definition
• insert_after_symbol: Insert code after a symbol definition

Rename Refactoring

• rename_symbol: Rename symbols with automatic reference updates across entire codebase

Pattern Search

• search_for_pattern: Regex search across project files

Project Memory

• read_memory: Retrieve project-specific code structure and conventions
• write_memory: Store project-specific code structure and conventions

Progressive Disclosure Pattern

1. Start with get_symbols_overview for a file (50-75% token savings vs full read)
2. Read only the function bodies you actually need with find_symbol + include_body=True
3. Use find_referencing_symbols to trace callers before modifying any symbol
4. Fall back to Read/Edit for non-Rust files

Token Budget

• get_symbols_overview saves 50-75% tokens compared to reading full source files
• Always prefer symbol-level reads over full-file reads for Rust code
• A single find_symbol call is cheaper than reading and searching a full file