Update fern definition (#2040)

Co-authored-by: tsbhangu <8963343+tsbhangu@users.noreply.github.com>

Author: dsinghvi

fern/apis/fai/openapi.json

@@ -6261,6 +6261,21 @@
             ],
             "description": "The model to use for the chat completion"
           },
+          "max_tokens": {
+            "anyOf": [
+              {
+                "type": "integer",
+                "maximum": 1000.0,
+                "minimum": 100.0
+              },
+              {
+                "type": "null"
+              }
+            ],
+            "title": "Max Tokens",
+            "description": "The maximum number of tokens to generate. Defaults to 1000. Note: setting a token count lower than 400 may result in incomplete responses. You can add a custom system prompt to let the model know the maximum token count it can use.",
+            "default": 1000
+          },
           "system_prompt": {
             "anyOf": [
               {