Struct CreateMessageRequestParams 

#[non_exhaustive]
pub struct CreateMessageRequestParams {
    pub meta: Option<RequestMetaObject>,
    pub messages: Vec<SamplingMessage>,
    pub model_preferences: Option<ModelPreferences>,
    pub system_prompt: Option<String>,
    pub include_context: Option<ContextInclusion>,
    pub temperature: Option<f32>,
    pub max_tokens: u32,
    pub stop_sequences: Option<Vec<String>>,
    pub metadata: Option<Value>,
    pub tools: Option<Vec<Tool>>,
    pub tool_choice: Option<ToolChoice>,
}

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Parameters for creating a message through LLM sampling.

This structure contains all the necessary information for a client to generate an LLM response, including conversation history, model preferences, and generation parameters.

This implements TaskAugmentedRequestParamsMeta as sampling requests can be long-running and may benefit from task-based execution.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

meta: Option<RequestMetaObject>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Protocol-level metadata for this request (SEP-1319)

messages: Vec<SamplingMessage>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

The conversation history and current messages

model_preferences: Option<ModelPreferences>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Preferences for model selection and behavior

system_prompt: Option<String>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

System prompt to guide the model’s behavior

include_context: Option<ContextInclusion>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

How much context to include from MCP servers

temperature: Option<f32>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Temperature for controlling randomness (0.0 to 1.0)

max_tokens: u32

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Maximum number of tokens to generate

stop_sequences: Option<Vec<String>>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Sequences that should stop generation

metadata: Option<Value>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Additional metadata for the request

tools: Option<Vec<Tool>>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Tools available for the model to call (SEP-1577)

tool_choice: Option<ToolChoice>

👎Deprecated since 2.0.0:

Sampling is deprecated by SEP-2577 and will be removed in a future release. See https://github.com/modelcontextprotocol/modelcontextprotocol/pull/2577

Tool selection behavior (SEP-1577)

Implementations

impl CreateMessageRequestParams

pub fn new(messages: Vec<SamplingMessage>, max_tokens: u32) -> Self

Create a new CreateMessageRequestParams with required fields.

pub fn with_model_preferences(self, model_preferences: ModelPreferences) -> Self

Set model preferences.

pub fn with_system_prompt(self, system_prompt: impl Into<String>) -> Self

Set system prompt.

pub fn with_include_context(self, include_context: ContextInclusion) -> Self

Set include context.

pub fn with_temperature(self, temperature: f32) -> Self

Set temperature.

pub fn with_stop_sequences(self, stop_sequences: Vec<String>) -> Self

Set stop sequences.

pub fn with_metadata(self, metadata: Value) -> Self

Set metadata.

pub fn with_tools(self, tools: Vec<Tool>) -> Self

Set tools.

pub fn with_tool_choice(self, tool_choice: ToolChoice) -> Self

Set tool choice.

pub fn validate(&self) -> Result<(), String>

Validate the sampling request parameters per SEP-1577 spec requirements.

Checks:

• ToolUse content is only allowed in assistant messages
• ToolResult content is only allowed in user messages
• Messages with tool result content MUST NOT contain other content types
• Every assistant ToolUse must be balanced with a corresponding user ToolResult

Trait Implementations

impl Clone for CreateMessageRequestParams

fn clone(&self) -> CreateMessageRequestParams

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CreateMessageRequestParams

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for CreateMessageRequestParams

fn default() -> CreateMessageRequestParams

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for CreateMessageRequestParams

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl JsonSchema for CreateMessageRequestParams

fn schema_name() -> Cow<'static, str>

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn inline_schema() -> bool

Whether JSON Schemas generated for this type should be included directly in parent schemas, rather than being re-used where possible using the $ref keyword.

impl PartialEq for CreateMessageRequestParams

fn eq(&self, other: &CreateMessageRequestParams) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl RequestParamsMeta for CreateMessageRequestParams

fn meta(&self) -> Option<&RequestMetaObject>

Get a reference to the meta field

fn meta_mut(&mut self) -> &mut Option<RequestMetaObject>

Get a mutable reference to the meta field

fn set_meta(&mut self, meta: RequestMetaObject)

Set the meta field

fn progress_token(&self) -> Option<ProgressToken>

Get the progress token from meta, if present

fn set_progress_token(&mut self, token: ProgressToken)

Set a progress token in meta

fn traceparent(&self) -> Option<&str>

Get the W3C traceparent value from meta, if present (SEP-414)

fn set_traceparent(&mut self, value: &str)

Set the W3C traceparent value in meta (SEP-414)

fn tracestate(&self) -> Option<&str>

Get the W3C tracestate value from meta, if present (SEP-414)

fn set_tracestate(&mut self, value: &str)

Set the W3C tracestate value in meta (SEP-414)

fn baggage(&self) -> Option<&str>

Get the W3C baggage value from meta, if present (SEP-414)

fn set_baggage(&mut self, value: &str)

Set the W3C baggage value in meta (SEP-414)

fn meta_or_default(&mut self) -> &mut RequestMetaObject

Get a mutable reference to meta, inserting an empty one if absent.

impl Serialize for CreateMessageRequestParams

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for CreateMessageRequestParams