diff --git a/vllm/config.py b/vllm/config.py
index 2d61552c5dadc..124d62b699771 100644
--- a/vllm/config.py
+++ b/vllm/config.py
@@ -1575,7 +1575,18 @@ class ModelConfig:
         return self.multimodal_config
 
     def try_get_generation_config(self) -> dict[str, Any]:
-        if self.generation_config in ("auto", "vllm"):
+        """
+        This method attempts to retrieve the non-default values of the
+        generation config for this model.
+        
+        The generation config can contain information about special tokens, as
+        well as sampling parameters. Which is why this method exists separately
+        to `get_diff_sampling_param`.
+
+        Returns:
+            A dictionary containing the non-default generation config.
+        """
+        if self.generation_config in {"auto", "vllm"}:
             config = try_get_generation_config(
                 self.hf_config_path or self.model,
                 trust_remote_code=self.trust_remote_code,
@@ -1594,13 +1605,18 @@ class ModelConfig:
 
     def get_diff_sampling_param(self) -> dict[str, Any]:
         """
-        This method returns a dictionary containing the parameters
-        that differ from the default sampling parameters. If
-        `generation_config` is `"vllm"`, an empty dictionary is returned.
+        This method returns a dictionary containing the non-default sampling
+        parameters with `override_generation_config` applied.
+
+        The default sampling parameters are:
+
+        - vLLM's neutral defaults if `self.generation_config="vllm"`
+        - the model's defaults if `self.generation_config="auto"`
+        - as defined in `generation_config.json` if
+            `self.generation_config="path/to/generation_config/dir"`
 
         Returns:
-            dict[str, Any]: A dictionary with the differing sampling
-            parameters, if `generation_config` is `"vllm"` an empty dictionary.
+            A dictionary containing the non-default sampling parameters.
         """
         if self.generation_config == "vllm":
             config = {}