Struct ToolCall 

pub struct ToolCall {
    pub id: String,
    pub call_type: String,
    pub function: Option<FunctionCall>,
    pub text: Option<String>,
    pub thought_signature: Option<String>,
}

Universal tool call that matches OpenAI/Anthropic/Gemini specifications

Fields

id: String

Unique identifier for this tool call (e.g., “call_123”)

call_type: String

The type of tool call: “function”, “custom” (GPT-5 freeform), or other

function: Option<FunctionCall>

Function call details (for function-type tools)

text: Option<String>

Raw text payload (for custom freeform tools in GPT-5)

thought_signature: Option<String>

Gemini-specific thought signature for maintaining reasoning context

Implementations

impl ToolCall

pub fn function(id: String, name: String, arguments: String) -> ToolCall

Create a new function tool call

pub fn function_with_namespace( id: String, namespace: Option<String>, name: String, arguments: String, ) -> ToolCall

Create a new function tool call with an optional namespace.

pub fn custom(id: String, name: String, text: String) -> ToolCall

Create a new custom tool call with raw text payload (GPT-5 freeform)

pub fn is_custom(&self) -> bool

Returns true when this tool call uses GPT-5 custom/freeform semantics.

pub fn tool_name(&self) -> Option<&str>

Returns the tool name when the call includes function details.

pub fn raw_input(&self) -> Option<&str>

Returns the raw payload text exactly as emitted by the model.

pub fn parsed_arguments(&self) -> Result<Value, Error>

Parse the arguments as JSON Value (for function-type tools)

pub fn execution_arguments(&self) -> Result<Value, Error>

Returns the execution payload for this tool call.

Function tools keep their JSON semantics. Custom tools execute with their raw text payload wrapped as a JSON string value so freeform inputs can flow through the existing tool pipeline.

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

Validate that this tool call is properly formed

Trait Implementations

impl Clone for ToolCall

fn clone(&self) -> ToolCall

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ToolCall

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ToolCall

fn deserialize<__D>( __deserializer: __D, ) -> Result<ToolCall, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for ToolCall

fn eq(&self, other: &ToolCall) -> 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 ToolCall

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ToolCall