Struct ChatToolCallStartAction 

pub struct ChatToolCallStartAction {
    pub turn_id: String,
    pub tool_call_id: String,
    pub meta: Option<JsonObject>,
    pub tool_name: String,
    pub display_name: String,
    pub intention: Option<String>,
    pub contributor: Option<ToolCallContributor>,
}

A tool call begins — parameters are streaming from the LM.

The server sets {@link ToolCallContributor | contributor} to identify the origin of the tool. For client-provided tools, the named client is responsible for executing the tool once it reaches the running state and dispatching chat/toolCallComplete. For MCP-served tools, the server executes the call against the named McpServerCustomization.

Fields

turn_id: String

Turn identifier

tool_call_id: String

Tool call identifier

meta: Option<JsonObject>

Additional provider-specific metadata for this tool call.

Clients MAY look for well-known keys here to provide enhanced UI. For example, a ptyTerminal key with { input: string; output: string } indicates the tool operated on a terminal (both input and output may contain escape sequences).

tool_name: String

Internal tool name (for debugging/logging)

display_name: String

Human-readable tool name

intention: Option<String>

Human-readable description of what the tool invocation intends to do

contributor: Option<ToolCallContributor>

Reference to the contributor of the tool being called. Absent for server-side tools that are not contributed by a client or MCP server.

Trait Implementations

impl Clone for ChatToolCallStartAction

fn clone(&self) -> ChatToolCallStartAction

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ChatToolCallStartAction

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ChatToolCallStartAction

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for ChatToolCallStartAction

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for ChatToolCallStartAction

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 ChatToolCallStartAction