Struct Step 

#[non_exhaustive]
pub struct Step {

    pub id: String,
    pub step_index: u32,
    pub trajectory_id: String,
    pub cascade_id: String,
    pub step_type: StepType,
    pub source: StepSource,
    pub target: StepTarget,
    pub status: StepStatus,
    pub content: String,
    pub content_delta: String,
    pub thinking: String,
    pub thinking_delta: String,
    pub tool_calls: Vec<ToolCallInfo>,
    pub error: String,
    pub http_code: u16,
    pub is_complete_response: Option<bool>,
    pub structured_output: Option<Value>,
    pub usage_metadata: Option<UsageMetadata>,
}

A single step in the agent trajectory, mirroring the SDK’s Step.

Construction

Step is #[non_exhaustive], so outside this crate it can only be built with the TypedBuilder. Every field defaults (matching Default), so callers set only the fields they care about:

use agy_bridge::Step;

let step = Step::builder()
    .id("traj:0")
    .content("Running command...")
    .build();
assert_eq!(step.id, "traj:0");
// Unset fields fall back to their defaults.
assert_eq!(step.step_index, 0);
assert!(step.tool_calls.is_empty());

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.

id: String

Unique string identifier for the step.

step_index: u32

Integer index of the step in the trajectory.

trajectory_id: String

Identifier of the trajectory this step belongs to.

The SDK’s connection layer assigns one trajectory id per agent trajectory. Compare with cascade_id to tell a primary-agent step (trajectory_id == cascade_id) apart from a subagent step (trajectory_id != cascade_id); see Step::is_subagent_step. Empty when the harness did not report one.

cascade_id: String

Identifier of the top-level cascade — i.e. the primary agent trajectory.

Every step in a turn, primary and subagent alike, shares the same cascade_id, so it identifies the parent trajectory. A step originates from a subagent when its trajectory_id differs from this value. Empty when the harness did not report one.

step_type: StepType

The high-level type of the step.

source: StepSource

The source that generated the step.

target: StepTarget

The target of the step interaction.

status: StepStatus

The status of the step.

content: String

The text content/output of the step.

content_delta: String

Incremental text content added since the last update for this step.

thinking: String

Full model reasoning/thinking text for planner responses.

thinking_delta: String

Incremental thinking text added since the last update for this step.

tool_calls: Vec<ToolCallInfo>

List of tool calls associated with the step.

error: String

Short error message if the step failed.

http_code: u16

HTTP status code from the harness error, if any (e.g. 400, 429, 503).

The SDK populates this from the harness’s error.http_code field. Used by error detection in forward_step_to_writer for logging.

is_complete_response: Option<bool>

Whether this step is a completed model response directed at the user.

Multiple steps per turn may have this flag set; consumers wanting only the last response should iterate fully.

structured_output: Option<Value>

Structured output payload extracted from the FINISH step.

This is serde_json::Value because it contains user-defined schema data whose shape is not known at compile time.

usage_metadata: Option<UsageMetadata>

Token usage for this step’s model invocation.

Implementations

impl Step

pub fn builder() -> StepBuilder<((), (), (), (), (), (), (), (), (), (), (), (), (), (), (), (), (), ())>

Create a builder for building Step. On the builder, call .id(...)(optional), .step_index(...)(optional), .trajectory_id(...)(optional), .cascade_id(...)(optional), .step_type(...)(optional), .source(...)(optional), .target(...)(optional), .status(...)(optional), .content(...)(optional), .content_delta(...)(optional), .thinking(...)(optional), .thinking_delta(...)(optional), .tool_calls(...)(optional), .error(...)(optional), .http_code(...)(optional), .is_complete_response(...)(optional), .structured_output(...)(optional), .usage_metadata(...)(optional) to set the values of the fields. Finally, call .build() to create the instance of Step.

impl Step

pub fn is_subagent_step(&self) -> bool

Whether this step originates from a subagent trajectory rather than the primary agent’s.

Mirrors the SDK’s own parent/subagent discrimination (cascade_id AND trajectory_id AND trajectory_id != cascade_id): a step is a subagent step only when it carries a known parent cascade_id and a trajectory_id that differs from it. Steps missing either id — e.g. from mocks or older harnesses — are treated as primary.

Trait Implementations

impl Clone for Step

fn clone(&self) -> Step

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Step

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

Formats the value using the given formatter.

impl Default for Step

fn default() -> Step

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Step

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Step

impl<'a, 'py> FromPyObject<'a, 'py> for Step

type Error = PyErr

The type returned in the event of a conversion error.

fn extract(ob: Borrowed<'a, 'py, PyAny>) -> PyResult<Self>

Extracts Self from the bound smart pointer obj.

impl PartialEq for Step

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Step

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 Step