correct channel related docs for slack (#557)

Author: ramsrib

fern/tools/slack.mdx

@@ -39,11 +39,10 @@ After connecting your Slack workspace, create the tool:
 3. Select **Slack** from the available options
 4. Choose the Slack Send Message Tool
 5. Provide a name and description explaining when it should be invoked
-6. Configure the tool with the following required fields:
-   - `channel`: The name of the Slack channel where messages will be sent (e.g., "#general" or "#notifications")
+6. In the description field, specify the Slack channel where messages should be sent (e.g., "Send urgent notifications to the #customer-support channel")
 
 <Note>
-  The description field is crucial as it helps the AI model understand when and how to use the tool. Be specific about the scenarios and conditions when the tool should be invoked.
+  The description field is crucial as it helps the AI model understand when and how to use the tool, and also specifies which channel to send messages to. Be specific about the scenarios, conditions, and target channel when the tool should be invoked.
 </Note>
 
 ### 3. Add Tool to Assistant
@@ -60,13 +59,13 @@ Now, add the Slack tool to your assistant:
 
 ### Slack Send Message Tool
 
-This tool uses the following fields to send messages to Slack:
+This tool sends messages to Slack channels based on the configuration specified in the tool's description:
 
-- `channel`: The name of the Slack channel where the message will be sent
-- `text`: The message content to be sent to the channel
+- The target channel is specified in the tool's description field
+- The message content is dynamically generated by the AI based on the conversation context
 
 <Note>
-  The channel name should be specified in the format "#channel-name". Make sure the bot has been added to the channel before sending messages.
+  The channel name should be specified in the description in the format "#channel-name". Make sure the bot has been added to the channel before sending messages.
 </Note>
 
 ## Example Usage
@@ -81,14 +80,14 @@ Here's how the tool can be used in your assistant's configuration:
     "messages": [
       {
         "role": "system",
-        "content": "You are a customer service assistant. When a customer requests a callback or needs urgent attention, use the Slack tool to notify the support team in the #customer-support channel. Include the following information in your message:\n\n- Customer name\n- Phone number\n- Reason for callback/urgent attention\n- Any specific time constraints\n\nAlways be professional and concise in your Slack messages."
+        "content": "You are a customer service assistant. When a customer requests a callback or needs urgent attention, use the Slack tool to notify the support team. Always be professional and concise in your Slack messages."
       }
     ],
     "tools": [
       {
         "type": "slack.message.send",
         "name": "notifySupport",
-        "description": "Use this tool to send urgent notifications to the support team in the #customer-support channel. Only use this when a customer needs immediate attention or requests a callback."
+        "description": "Send urgent notifications to the #customer-support channel when a customer needs immediate attention or requests a callback. Include customer name, phone number, reason for callback, and any time constraints."
       }
     ]
   }