Enum Item 

pub enum Item {
    Message(MessageItem),
    FileSearchCall(FileSearchToolCall),
    ComputerCall(ComputerToolCall),
    ComputerCallOutput(ComputerCallOutputItemParam),
    WebSearchCall(WebSearchToolCall),
    FunctionCall(FunctionToolCall),
    FunctionCallOutput(FunctionCallOutputItemParam),
    Reasoning(ReasoningItem),
    ImageGenerationCall(ImageGenToolCall),
    CodeInterpreterCall(CodeInterpreterToolCall),
    LocalShellCall(LocalShellToolCall),
    LocalShellCallOutput(LocalShellToolCallOutput),
    McpListTools(MCPListTools),
    McpApprovalRequest(MCPApprovalRequest),
    McpApprovalResponse(MCPApprovalResponse),
    McpCall(MCPToolCall),
    CustomToolCallOutput(CustomToolCallOutput),
    CustomToolCall(CustomToolCall),
}

Content item used to generate a response.

This is a properly discriminated union based on the type field, using Rust’s type-safe enum with serde’s tag attribute for efficient deserialization.

OpenAPI Specification

Corresponds to the Item schema in the OpenAPI spec with a type discriminator.

Variants

Message(MessageItem)

A message (type: “message”). Can represent InputMessage (user/system/developer) or OutputMessage (assistant).

InputMessage: A message input to the model with a role indicating instruction following hierarchy. Instructions given with the developer or system role take precedence over instructions given with the user role. OutputMessage: A message output from the model.

FileSearchCall(FileSearchToolCall)

The results of a file search tool call. See the file search guide for more information.

ComputerCall(ComputerToolCall)

A tool call to a computer use tool. See the computer use guide for more information.

ComputerCallOutput(ComputerCallOutputItemParam)

The output of a computer tool call.

WebSearchCall(WebSearchToolCall)

The results of a web search tool call. See the web search guide for more information.

FunctionCall(FunctionToolCall)

A tool call to run a function. See the

function calling guide for more information.

FunctionCallOutput(FunctionCallOutputItemParam)

The output of a function tool call.

Reasoning(ReasoningItem)

A description of the chain of thought used by a reasoning model while generating a response. Be sure to include these items in your input to the Responses API for subsequent turns of a conversation if you are manually managing context.

ImageGenerationCall(ImageGenToolCall)

An image generation request made by the model.

CodeInterpreterCall(CodeInterpreterToolCall)

A tool call to run code.

LocalShellCall(LocalShellToolCall)

A tool call to run a command on the local shell.

LocalShellCallOutput(LocalShellToolCallOutput)

The output of a local shell tool call.

McpListTools(MCPListTools)

A list of tools available on an MCP server.

McpApprovalRequest(MCPApprovalRequest)

A request for human approval of a tool invocation.

McpApprovalResponse(MCPApprovalResponse)

A response to an MCP approval request.

McpCall(MCPToolCall)

An invocation of a tool on an MCP server.

CustomToolCallOutput(CustomToolCallOutput)

The output of a custom tool call from your code, being sent back to the model.

CustomToolCall(CustomToolCall)

A call to a custom tool created by the model.

Trait Implementations

impl Clone for Item

fn clone(&self) -> Item

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Item

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Item

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Item

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

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 Item