search-tools

```

Need CONCEPTUAL/SEMANTIC search?

(how does X work, find patterns, understand architecture)

→ Use LEANN (/leann-search) - embedding-based semantic search

→ PreToolUse hook auto-redirects semantic Grep queries

Need to understand code STRUCTURE?

(find function calls, class usages, refactor patterns)

→ Use AST-grep (/ast-grep-find)

Need to find TEXT in code?

→ Use Morph (/morph-search) - 20x faster

→ If no Morph API key: fall back to Grep tool

Simple one-off search?

→ Use built-in Grep tool directly

```

| Tool | Best For | Requires |

|------|----------|----------|

| LEANN | Semantic search: "how does caching work", "error handling patterns", conceptual queries | Index built |

| AST-grep | Structural patterns: "find all calls to foo()", refactoring, find usages by type | MCP server |

| Morph | Fast text search: "find files mentioning error", grep across codebase | API key |

| Grep | Literal patterns, class/function names, regex | Nothing (built-in) |

LEANN (semantic/conceptual):

• "how does authentication work"
• "find error handling patterns"
• "where is rate limiting implemented"

AST-grep (structural):

• "Find all functions that return a Promise"
• "Find all React components using useState"
• "Refactor all imports of X to Y"

Morph (text search):

• "Find all files mentioning 'authentication'"
• "Search for TODO comments"

Grep (literal):

• class ProviderAdapter
• def __init__
• Regex patterns

```bash

# Search with semantic query

leann search opc-dev "how does blackboard communication work" --top-k 5

# List available indexes

leann list

# Rebuild index (when code changes)

leann build opc-dev --docs dir1 dir2 --no-recompute --no-compact --force

```