> For the complete documentation index, see [llms.txt](https://docs.flowiseai.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flowiseai.com/integrations/llamaindex/response-synthesizer.md).

# Response Synthesizer

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Response Synthesizer nodes are responsible for sending the query, nodes, and prompt templates to the LLM to generate a response. There are 4 modes for generating a response:

### Synthesizer Nodes:

* [Refine](/integrations/llamaindex/response-synthesizer/refine.md)
* [Compact and Refine](/integrations/llamaindex/response-synthesizer/compact-and-refine.md)
* [Simple Response Builder](/integrations/llamaindex/response-synthesizer/simple-response-builder.md)
* [Tree Summarize](/integrations/llamaindex/response-synthesizer/tree-summarize.md)