Struct ToolExecutionResult 

#[non_exhaustive]
pub struct ToolExecutionResult { /* private fields */ }

The full structured result of a single tool execution.

This is what the dynamic tool boundary (ToolDyn) produces and what flows through to the StepEvent::ToolResult hook event. It keeps the three concerns separate:

• model_output: the text delivered to the model;
• outcome: the structured ToolOutcome;
• extensions: metadata never sent to the model.

Tool authors rarely build this directly — they return a ToolReturn and the boundary assembles it. In a manual ToolDyn implementation construct one with success / failed / denied; read it back with the model_output / outcome / extensions accessors.

The fields are crate-private on purpose: Skipped is a framework-only outcome (a hook Flow::Skip), and there is no public constructor or setter that yields it — a tool that ran was not skipped. See the ToolOutcome note.

Implementations

impl ToolExecutionResult

pub fn success(model_output: impl Into<String>) -> Self

A successful result whose model output is model_output verbatim.

pub fn failed(model_output: impl Into<String>, failure: ToolFailure) -> Self

A failed result: model_output is the model-visible feedback, failure the structured classification.

pub fn denied(model_output: impl Into<String>) -> Self

A Denied result: the tool refused the call (the body did not run to completion). The tool-authored counterpart to a hook Flow::Skip; see the ToolOutcome note.

pub fn with_extensions(self, extensions: ToolResultExtensions) -> Self

Attach result extensions, replacing any already set.

pub fn with_extension<E: Clone + WasmCompatSend + WasmCompatSync + 'static>( self, extension: E, ) -> Self

Insert a single value into the result extensions, returning the updated result. The single-value counterpart to with_extensions, mirroring ToolReturn::with_extension for manual ToolDyn implementations.

pub fn model_output(&self) -> &str

The text delivered to the model as the tool result. Present even for a failure, so the model gets useful feedback (a handled error message).

pub fn outcome(&self) -> &ToolOutcome

The structured ToolOutcome of the call.

pub fn extensions(&self) -> &ToolResultExtensions

Metadata attached by the tool, surfaced to hooks/tracing but never sent to the model.

Trait Implementations

impl Clone for ToolExecutionResult

fn clone(&self) -> ToolExecutionResult

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ToolExecutionResult

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

Formats the value using the given formatter.