[Bugfix][Frontend] Fix validation of logprobs in ChatCompletionRequest (vllm-project#14352)

schoennenbeck · Mu Huai · commit b5fc1099ea7b · 2025-05-12T19:19:05.000+08:00
Signed-off-by: Sebastian Schönnenbeck &lt;sebastian.schoennenbeck@comma-soft.com&gt;
Signed-off-by: Mu Huai &lt;tianbowen.tbw@antgroup.com&gt;
diff --git a/vllm/entrypoints/openai/protocol.py b/vllm/entrypoints/openai/protocol.py
@@ -548,7 +548,7 @@ def check_logprobs(cls, data):
             if top_logprobs < 0:
                 raise ValueError("`top_logprobs` must be a positive value.")
 
-            if not data.get("logprobs"):
+            if top_logprobs > 0 and not data.get("logprobs"):
                 raise ValueError(
                     "when using `top_logprobs`, `logprobs` must be set to true."
                 )

Original file line number	Diff line number	Diff line change
`@@ -548,7 +548,7 @@ def check_logprobs(cls, data):`
`548`	`548`	`if top_logprobs < 0:`
`549`	`549`	raise ValueError("`top_logprobs` must be a positive value.")
`550`	`550`
`551`		`- if not data.get("logprobs"):`
	`551`	`+ if top_logprobs > 0 and not data.get("logprobs"):`
`552`	`552`	`raise ValueError(`
`553`	`553`	"when using `top_logprobs`, `logprobs` must be set to true."
`554`	`554`	`)`