diff --git a/lua/gp/dispatcher.lua b/lua/gp/dispatcher.lua
index d4214aa..cebaf30 100644
--- a/lua/gp/dispatcher.lua
+++ b/lua/gp/dispatcher.lua
@@ -169,7 +169,7 @@ D.prepare_payload = function(messages, model, provider)
 		model = model.model,
 		stream = true,
 		messages = messages,
-		max_tokens = model.max_tokens or 4096,
+		max_completion_tokens = model.max_completion_tokens or 4096,
 		temperature = math.max(0, math.min(2, model.temperature or 1)),
 		top_p = math.max(0, math.min(1, model.top_p or 1)),
 	}
@@ -185,7 +185,7 @@ D.prepare_payload = function(messages, model, provider)
 			end
 		end
 		-- remove max_tokens, top_p, temperature for o1 models. https://platform.openai.com/docs/guides/reasoning/beta-limitations
-		output.max_tokens = nil
+		output.max_completion_tokens = nil
 		output.temperature = nil
 		output.top_p = nil
 	end