> ## Documentation Index
> Fetch the complete documentation index at: https://praison.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# QueryRewriterAgent Module

> Transform user queries to improve retrieval quality in RAG applications

# QueryRewriterAgent Module

The `QueryRewriterAgent` class transforms user queries to improve retrieval quality in RAG applications.

## Supported Strategies

* **BASIC**: Simple rephrasing for clarity and keyword optimization
* **HYDE**: Hypothetical Document Embeddings - generates a hypothetical answer
* **STEP\_BACK**: Generates higher-level concept questions for complex queries
* **SUB\_QUERIES**: Decomposes multi-part questions into focused sub-queries
* **MULTI\_QUERY**: Generates multiple paraphrased versions for ensemble retrieval
* **CONTEXTUAL**: Uses conversation history to resolve references and context
* **AUTO**: Automatically selects the best strategy

## Import

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import QueryRewriterAgent, RewriteStrategy
```

## Quick Example

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import QueryRewriterAgent, RewriteStrategy

agent = QueryRewriterAgent()

# Basic rewriting
result = agent.rewrite("AI trends")
print(result.rewritten_queries)

# HyDE for better semantic matching
result = agent.rewrite(
    "What is quantum computing?",
    strategy=RewriteStrategy.HYDE
)
print(result.hypothetical_document)
```

## Constructor

### `QueryRewriterAgent()`

Creates a new QueryRewriterAgent instance.

**Parameters:**

| Parameter | Type   | Default            | Description                                |
| --------- | ------ | ------------------ | ------------------------------------------ |
| `name`    | `str`  | `"Query Rewriter"` | Agent name                                 |
| `model`   | `str`  | `"gpt-4o-mini"`    | LLM model to use                           |
| `verbose` | `bool` | `False`            | Enable verbose logging                     |
| `tools`   | `list` | `[]`               | Optional tools for context-aware rewriting |

## Methods

### `rewrite(query, strategy, chat_history)`

Rewrites a query using the specified strategy.

**Parameters:**

* `query` (str): The original user query
* `strategy` (RewriteStrategy): Rewriting strategy to use (default: AUTO)
* `chat_history` (list): Optional conversation history for contextual rewriting

**Returns:** `RewriteResult` - Contains rewritten queries and metadata

## RewriteStrategy Enum

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
class RewriteStrategy(Enum):
    BASIC = "basic"
    HYDE = "hyde"
    STEP_BACK = "step_back"
    SUB_QUERIES = "sub_queries"
    MULTI_QUERY = "multi_query"
    CONTEXTUAL = "contextual"
    AUTO = "auto"
```

## RewriteResult

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
@dataclass
class RewriteResult:
    original_query: str
    rewritten_queries: List[str]
    strategy_used: RewriteStrategy
    hypothetical_document: Optional[str] = None
    step_back_question: Optional[str] = None
    sub_queries: Optional[List[str]] = None
    metadata: Dict[str, Any]
    
    @property
    def primary_query(self) -> str:
        """Returns the primary rewritten query."""
        
    @property
    def all_queries(self) -> List[str]:
        """Returns all queries including original and rewritten."""
```

## Examples

### Contextual Rewriting with Chat History

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import QueryRewriterAgent

agent = QueryRewriterAgent()

chat_history = [
    {"role": "user", "content": "Tell me about Python"},
    {"role": "assistant", "content": "Python is a programming language..."}
]

result = agent.rewrite(
    "What about its performance?",
    chat_history=chat_history
)
# Resolves "its" to "Python's"
```

### With Search Tools

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import QueryRewriterAgent
from praisonaiagents import internet_search

agent = QueryRewriterAgent(tools=[internet_search], )
result = agent.rewrite("latest AI developments")
# Searches first, then rewrites with context
```

## Related

* [Agent Module](/docs/sdk/praisonaiagents/agent/agent) - Base Agent class
* [PromptExpanderAgent Module](/docs/sdk/praisonaiagents/agent/prompt_expander_agent) - Expand prompts for tasks
* [Knowledge Module](/docs/sdk/praisonaiagents/knowledge/knowledge) - Knowledge base integration