llama_cpp server: define fields for chat completions

Slight refactor for common fields shared between completion and chat completion

llama_cpp/server/app.py

@@ -70,6 +70,55 @@ model_field = Field(
     description="The model to use for generating completions."
 )
 
+max_tokens_field = Field(
+    default=16,
+    ge=1,
+    le=2048,
+    description="The maximum number of tokens to generate."
+)
+
+temperature_field = Field(
+    default=0.8,
+    ge=0.0,
+    le=2.0,
+    description="Adjust the randomness of the generated text.\n\n" +
+    "Temperature is a hyperparameter that controls the randomness of the generated text. It affects the probability distribution of the model's output tokens. A higher temperature (e.g., 1.5) makes the output more random and creative, while a lower temperature (e.g., 0.5) makes the output more focused, deterministic, and conservative. The default value is 0.8, which provides a balance between randomness and determinism. At the extreme, a temperature of 0 will always pick the most likely next token, leading to identical outputs in each run."
+)
+
+top_p_field = Field(
+    default=0.95,
+    ge=0.0,
+    le=1.0,
+    description="Limit the next token selection to a subset of tokens with a cumulative probability above a threshold P.\n\n" +
+    "Top-p sampling, also known as nucleus sampling, is another text generation method that selects the next token from a subset of tokens that together have a cumulative probability of at least p. This method provides a balance between diversity and quality by considering both the probabilities of tokens and the number of tokens to sample from. A higher value for top_p (e.g., 0.95) will lead to more diverse text, while a lower value (e.g., 0.5) will generate more focused and conservative text."
+)
+
+stop_field = Field(
+    default=None,
+    description="A list of tokens at which to stop generation. If None, no stop tokens are used."
+)
+
+stream_field = Field(
+    default=False,
+    description="Whether to stream the results as they are generated. Useful for chatbots."
+)
+
+top_k_field = Field(
+    default=40,
+    ge=0,
+    description="Limit the next token selection to the K most probable tokens.\n\n" +
+    "Top-k sampling is a text generation method that selects the next token only from the top k most likely tokens predicted by the model. It helps reduce the risk of generating low-probability or nonsensical tokens, but it may also limit the diversity of the output. A higher value for top_k (e.g., 100) will consider more tokens and lead to more diverse text, while a lower value (e.g., 10) will focus on the most probable tokens and generate more conservative text."
+)
+
+repeat_penalty_field = Field(
+    default=1.0,
+    ge=0.0,
+    description="A penalty applied to each token that is already generated. This helps prevent the model from repeating itself.\n\n" +
+    "Repeat penalty is a hyperparameter used to penalize the repetition of token sequences during text generation. It helps prevent the model from generating repetitive or monotonous text. A higher value (e.g., 1.5) will penalize repetitions more strongly, while a lower value (e.g., 0.9) will be more lenient."
+)
+
+
+
 class CreateCompletionRequest(BaseModel):
     prompt: Union[str, List[str]] = Field(
         default="",
@@ -79,62 +128,27 @@ class CreateCompletionRequest(BaseModel):
         default=None,
         description="A suffix to append to the generated text. If None, no suffix is appended. Useful for chatbots."
     )
-    max_tokens: int = Field(
+    max_tokens: int = max_tokens_field
-        default=16,
+    temperature: float = temperature_field
-        ge=1,
+    top_p: float = top_p_field
-        le=2048,
-        description="The maximum number of tokens to generate."
-    )
-    temperature: float = Field(
-        default=0.8,
-        ge=0.0,
-        le=2.0,
-        description="Adjust the randomness of the generated text.\n\n" +
-        "Temperature is a hyperparameter that controls the randomness of the generated text. It affects the probability distribution of the model's output tokens. A higher temperature (e.g., 1.5) makes the output more random and creative, while a lower temperature (e.g., 0.5) makes the output more focused, deterministic, and conservative. The default value is 0.8, which provides a balance between randomness and determinism. At the extreme, a temperature of 0 will always pick the most likely next token, leading to identical outputs in each run."
-    )
-    top_p: float = Field(
-        default=0.95,
-        ge=0.0,
-        le=1.0,
-        description="Limit the next token selection to a subset of tokens with a cumulative probability above a threshold P.\n\n" +
-        "Top-p sampling, also known as nucleus sampling, is another text generation method that selects the next token from a subset of tokens that together have a cumulative probability of at least p. This method provides a balance between diversity and quality by considering both the probabilities of tokens and the number of tokens to sample from. A higher value for top_p (e.g., 0.95) will lead to more diverse text, while a lower value (e.g., 0.5) will generate more focused and conservative text."
-    )
     echo: bool = Field(
         default=False,
         description="Whether to echo the prompt in the generated text. Useful for chatbots."
     )
-    stop: Optional[List[str]] = Field(
+    stop: Optional[List[str]] = stop_field
-        default=None,
+    stream: bool = stream_field
-        description="A list of tokens at which to stop generation. If None, no stop tokens are used."
-    )
-    stream: bool = Field(
-        default=False,
-        description="Whether to stream the results as they are generated. Useful for chatbots."
-    )
     logprobs: Optional[int] = Field(
         default=None,
         ge=0,
         description="The number of logprobs to generate. If None, no logprobs are generated."
     )
 
-
-
     # ignored, but marked as required for the sake of compatibility with openai's api
     model: str = model_field
 
     # llama.cpp specific parameters
-    top_k: int = Field(
+    top_k: int = top_k_field
-        default=40,
+    repeat_penalty: float = repeat_penalty_field
-        ge=0,
-        description="Limit the next token selection to the K most probable tokens.\n\n" +
-        "Top-k sampling is a text generation method that selects the next token only from the top k most likely tokens predicted by the model. It helps reduce the risk of generating low-probability or nonsensical tokens, but it may also limit the diversity of the output. A higher value for top_k (e.g., 100) will consider more tokens and lead to more diverse text, while a lower value (e.g., 10) will focus on the most probable tokens and generate more conservative text."
-    )
-    repeat_penalty: float = Field(
-        default=1.0,
-        ge=0.0,
-        description="A penalty applied to each token that is already generated. This helps prevent the model from repeating itself.\n\n" +
-        "Repeat penalty is a hyperparameter used to penalize the repetition of token sequences during text generation. It helps prevent the model from generating repetitive or monotonous text. A higher value (e.g., 1.5) will penalize repetitions more strongly, while a lower value (e.g., 0.9) will be more lenient."
-    )
 
     class Config:
         schema_extra = {
@@ -199,26 +213,29 @@ def create_embedding(
 
 
 class ChatCompletionRequestMessage(BaseModel):
-    role: Union[Literal["system"], Literal["user"], Literal["assistant"]]
+    role: Union[Literal["system"], Literal["user"], Literal["assistant"]] = Field(
-    content: str
+        default=Literal["user"], description="The role of the message."
-    user: Optional[str] = None
+    )
+    content: str = Field(default="", description="The content of the message.")
 
 
 class CreateChatCompletionRequest(BaseModel):
-    model: Optional[str]
+    messages: List[ChatCompletionRequestMessage] = Field(
-    messages: List[ChatCompletionRequestMessage]
+        default=[],
-    temperature: float = 0.8
+        description="A list of messages to generate completions for."
-    top_p: float = 0.95
+    )
-    stream: bool = False
+    max_tokens: int = max_tokens_field
-    stop: Optional[List[str]] = []
+    temperature: float = temperature_field
-    max_tokens: int = 128
+    top_p: float = top_p_field
+    stop: Optional[List[str]] = stop_field
+    stream: bool = stream_field
 
     # ignored, but marked as required for the sake of compatibility with openai's api
     model: str = model_field
 
     # llama.cpp specific parameters
-    top_k: int = 40,
+    top_k: int = top_k_field
-    repeat_penalty: float = 1.1
+    repeat_penalty: float = repeat_penalty_field
 
     class Config:
         schema_extra = {