cs

cs (Codespelunker) is a sophisticated code search tool that goes beyond simple pattern matching. It understands code structure, distinguishing between code, comments, and strings, and ranks results by relevance using context-aware signals like cyclomatic complexity and file location.

cs doesn't require an index and can search code on-the-fly with intelligent ranking. It uses BM25 relevance scoring while automatically dampening test files and boosting matches based on location. The tool offers multiple interfaces: a console output mode, a built-in TUI (Terminal User Interface), an HTTP server with syntax highlighting, and even an MCP server for integration.

Advanced filtering options let you search specifically in code, comments, strings, declarations, or usages. You can combine multiple search terms with boolean operators (AND, OR, NOT), use regex patterns, and leverage fuzzy matching for flexible searching.

Basic usage

# Search for a term across code files.
cs myfunction

# Search only in code, excluding comments and strings.
cs --only-code pattern

# Start the interactive TUI interface.
cs -i searchterm

# Filter by language and search declarations only.
cs --only-declarations --lang go MyType