Knowledge base tool

The Knowledge base tool lets your agent query data from the Knowledge base from within the Agent step. It’s useful when you want the agent to look up information on demand - like answering FAQs, pulling product details, or referencing company docs - then incorporate this information into human-sounding responses.

Querying the knowledge base from inside the Agent step

ℹ️

This is our recommended approach to querying the knowledge base, as it allows your agent to automatically interpret the information retrieved and turn it into human-readable responses.

To enable querying the knowledge base from inside an Agent step, open your Agent step then turn on the Knowledge base toggle on the sidebar of the Agent popup.

Once enabled, you can also choose to set the tool's LLM description. This tells your agent when to query the knowledge base. If you're using the knowledge base to store a specialized type of data - such as product information - we recommend updating the default instructions to be more specific.

The following advanced query settings are also available:

• Query - by default, Voiceflow will use the user's last message as the query used to search the knowledge base. You can override this behaviour by providing a custom query. Please note that the exact query entered into this box will be used - this isn't an input where you should enter a prompt!
• Chunk limit - this determines the maximum number of chunks that can be returned by the knowledge base. By default, three chunks will be returned.
• Metadata filtering - if you set custom metadata when importing data to your knowledge base, you can filter your agent's querying using this option. To do so, press the plus button and select a metadata key that exists in your imported data. Then, either enter a default value (to force a specific value to be used), or set the LLM description (to allow the agent to dynamically set this value).

Using the KB search step

While we don't recommend using it, the legacy KB search step is available if you'd like to manually query the knowledge base from outside the Agent step. If you do this, you'll also need to pass queried response into the Prompt step as a variable to generate a useful response.