> ## Documentation Index > Fetch the complete documentation index at: https://docs.cassidyai.com/llms.txt > Use this file to discover all available pages before exploring further. # Update Knowledge Base document > Update an existing document in your Knowledge Base from within a Workflow. Update an existing document in your [Knowledge Base](/knowledge-base/overview) from within a [Workflow](/workflows/overview). Use this to keep documentation current automatically — for example, appending meeting notes to a running document or updating a FAQ page. In the Workflow builder, click **+** between blocks and select **Update Knowledge Base Document** from the action library. Action library with Update Knowledge Base Document selected Update Knowledge Base Document action added to the Workflow Choose how to reference the document using one of three options: * **Static Document** — Select a specific document directly from your Knowledge Base. Best for keeping a running document like a feedback log. Static Document selection from Knowledge Base * **Knowledge Base Item Reference** — Use a variable that references a Knowledge Base item. Useful when the document to update is a trigger input — for example, augmenting an existing document with a generated summary or FAQ. Knowledge Base Item Reference variable selector * **Dynamic Path** — Specify a document path using variables or naming conventions. Select the **Knowledge Base Collection**, enter the **Document Path** separated by forward slashes, and toggle **Create if Not Found** to create the document and any missing folders if they don't exist. Dynamic Path with Collection, Document Path, and Create if Not Found toggle Choose how the new content should be applied to the existing document: * **Replace entire document** — Completely replaces the existing content with new content * **Append to end** — Adds new content after the existing content * **Prepend to beginning** — Adds new content before the existing content Update method dropdown with Replace, Append, and Prepend options Specify the text to update the document with. Use **#** to [insert variables](/guides/prompt-engineering#workflow-prompts) from previous steps or the trigger to dynamically generate the content. Document Content field with variable reference ## Related * [Create Knowledge Base Document](/reference/actions/create-knowledge-base-document) * [Knowledge Base overview](/knowledge-base/overview)