---
title: Response Synthesis Modules | Developer Documentation
---

Detailed inputs/outputs for each response synthesizer are found below.

## API Example

The following shows the setup for utilizing all kwargs.

- `response_mode` specifies which response synthesizer to use
- `service_context` defines the LLM and related settings for synthesis
- `text_qa_template` and `refine_template` are the prompts used at various stages
- `use_async` is used for only the `tree_summarize` response mode right now, to asynchronously build the summary tree
- `streaming` configures whether to return a streaming response object or not
- `structured_answer_filtering` enables the active filtering of text chunks that are not relevant to a given question

In the `synthesize`/`asyntheszie` functions, you can optionally provide additional source nodes, which will be added to the `response.source_nodes` list.

```
from llama_index.core.data_structs import Node
from llama_index.core.schema import NodeWithScore
from llama_index.core import get_response_synthesizer


response_synthesizer = get_response_synthesizer(
    response_mode="refine",
    service_context=service_context,
    text_qa_template=text_qa_template,
    refine_template=refine_template,
    use_async=False,
    streaming=False,
)


# synchronous
response = response_synthesizer.synthesize(
    "query string",
    nodes=[NodeWithScore(node=Node(text="text"), score=1.0), ...],
    additional_source_nodes=[
        NodeWithScore(node=Node(text="text"), score=1.0),
        ...,
    ],
)


# asynchronous
response = await response_synthesizer.asynthesize(
    "query string",
    nodes=[NodeWithScore(node=Node(text="text"), score=1.0), ...],
    additional_source_nodes=[
        NodeWithScore(node=Node(text="text"), score=1.0),
        ...,
    ],
)
```

You can also directly return a string, using the lower-level `get_response` and `aget_response` functions

```
response_str = response_synthesizer.get_response(
    "query string", text_chunks=["text1", "text2", ...]
)
```

## Example Notebooks

- [Refine](/python/examples/response_synthesizers/refine/index.md)
- [Structured Refine](/python/examples/response_synthesizers/structured_refine/index.md)
- [Tree Summarize](/python/examples/response_synthesizers/tree_summarize/index.md)
- [Custom Prompting](/python/examples/response_synthesizers/custom_prompt_synthesizer/index.md)