Update agent.mdx

en/guides/workflow/node/agent.mdx

@@ -82,6 +82,44 @@ Enabling the **Memory** toggle empowers the Agent to retain and recall conversat
 
 For example, when users employ pronouns (such as “it”, “this”, or “they”) in subsequent messages, an Agent with Memory enabled can understand what these pronouns refer to from previous context without requiring users to restate complete information.
 
+
+## Customizing MCP Tools for Your Use Case
+
+When you add an MCP tool to an agent node or agent, you can customize how it behaves:
+
+<img
+  src="/images/CleanShot2025-07-07at07.41.33@2x.png"
+  alt="CleanShot 2025-07-07 at 07.41.33@2x.png"
+  title="CleanShot 2025-07-07 at 07.41.33@2x.png"
+  className="mx-auto"
+  style={{ width:"57%" }}
+/>
+
+### Tool Description
+
+You can override the default description that comes from the MCP server. This is useful for making the description more specific to your use case.
+
+### Parameter Configuration (Reasoning Config)
+
+For each tool parameter, you can choose between:
+
+**Auto**: Let the AI model determine the parameter value based on context (default behavior)
+
+**Fixed Value**: Set a specific value (can be a static value or a variable) that will always be used, removing the parameter from AI inference
+
+This is powerful for:
+
+- Setting consistent configuration values (like `numResults: 10` for search tools)
+- Pre-filling parameters that shouldn't change (like specific API endpoints or format preferences)
+- Simplifying tool usage by reducing the number of parameters the AI needs to handle
+
+For example, with a web search tool, you might:
+
+- Keep `query` on "Auto" so the AI determines what to search for
+- Set `numResults` to a fixed value like "5" to limit response size
+- Set other parameters like search filters to fixed values for consistent behavior
+
+
 <video controls src="https://assets-docs.dify.ai/2025/04/1801b96763eb8f22f1e2158645897885.mp4" width="100%"></video>
 
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