---
title: "SerperDevWebSearch"
id: serperdevwebsearch
slug: "/serperdevwebsearch"
description: "Search engine using SerperDev API."
---
# SerperDevWebSearch
Search engine using SerperDev API.
| | |
| --- | --- |
| **Most common position in a pipeline** | Before [`LinkContentFetcher`](../fetchers/linkcontentfetcher.mdx) or [Converters](../converters.mdx) |
| **Mandatory init variables** | "api_key": The SearchAPI API key. Can be set with `SERPERDEV_API_KEY` env var. |
| **Mandatory run variables** | “query”: A string with your query |
| **Output variables** | “documents”: A list of documents
”links”: A list of strings of resulting links |
| **API reference** | [Websearch](/reference/websearch-api) |
| **GitHub link** | https://github.com/deepset-ai/haystack/blob/main/haystack/components/websearch/serper_dev.py |
## Overview
When you give `SerperDevWebSearch` a query, it returns a list of the URLs most relevant to your search. It uses page snippets (pieces of text displayed under the page title in search results) to find the answers, not the whole pages.
To search the content of the web pages, use the [`LinkContentFetcher`](../fetchers/linkcontentfetcher.mdx) component.
`SerperDevWebSearch` requires a [SerperDev](https://serper.dev/) key to work. It uses a `SERPERDEV_API_KEY` environment variable by default. Otherwise, you can pass an `api_key` at initialization – see code examples below.
:::note
Alternative search
To use [Search API](https://www.searchapi.io/) as an alternative, see its respective [documentation page](/docs/searchapiwebsearch).
:::
## Usage
### On its own
This is an example of how `SerperDevWebSearch` looks up answers to our query on the web and converts the results into a list of documents with content snippets of the results, as well as URLs as strings.
```python
from haystack.components.websearch import SerperDevWebSearch
from haystack.utils import Secret
web_search = SerperDevWebSearch(api_key=Secret.from_token(""))
query = "What is the capital of Germany?"
response = web_search.run(query)
```
### In a pipeline
Here’s an example of a RAG pipeline where we use a `SerperDevWebSearch` to look up the answer to the query. The resulting documents are then passed to `LinkContentFetcher` to get the full text from the URLs. Finally, `PromptBuilder` and `OpenAIGenerator` work together to form the final answer.
```python
from haystack import Pipeline
from haystack.utils import Secret
from haystack.components.builders.chat_prompt_builder import ChatPromptBuilder
from haystack.components.fetchers import LinkContentFetcher
from haystack.components.converters import HTMLToDocument
from haystack.components.generators.chat import OpenAIChatGenerator
from haystack.components.websearch import SerperDevWebSearch
from haystack.dataclasses import ChatMessage
from haystack.utils import Secret
web_search = SerperDevWebSearch(api_key=Secret.from_token(""), top_k=2)
link_content = LinkContentFetcher()
html_converter = HTMLToDocument()
prompt_template = [
ChatMessage.from_system("You are a helpful assistant."),
ChatMessage.from_user(
"Given the information below:\n"
"{% for document in documents %}{{ document.content }}{% endfor %}\n"
"Answer question: {{ query }}.\nAnswer:"
)
]
prompt_builder = ChatPromptBuilder(template=prompt_template, required_variables={"query", "documents"})
llm = OpenAIChatGenerator(api_key=Secret.from_token(""), model="gpt-3.5-turbo")
pipe = Pipeline()
pipe.add_component("search", web_search)
pipe.add_component("fetcher", link_content)
pipe.add_component("converter", html_converter)
pipe.add_component("prompt_builder", prompt_builder)
pipe.add_component("llm", llm)
pipe.connect("search.links", "fetcher.urls")
pipe.connect("fetcher.streams", "converter.sources")
pipe.connect("converter.documents", "prompt_builder.documents")
pipe.connect("prompt_builder.messages", "llm.messages")
query = "What is the most famous landmark in Berlin?"
pipe.run(data={"search": {"query": query}, "prompt_builder": {"query": query}})
```
## Additional References
:notebook: Tutorial: [Building Fallbacks to Websearch with Conditional Routing](https://haystack.deepset.ai/tutorials/36_building_fallbacks_with_conditional_routing)