Enum ItemKind 

pub enum ItemKind {
    System,
    Developer,
    User,
    Assistant,
    Tool,
    Context,
    Notification,
}

The role of an Item in the transcript.

Variants are ordered so that System < Developer < User < Assistant < Tool < Context < Notification, which is useful for sorting items by priority during compaction.

Variants

System

Instructions provided by the application author (highest priority).

Developer

Developer-level instructions that sit between system and user.

User

A message from the end user.

Assistant

A response generated by the model.

Tool

Output from a tool execution.

Context

Ambient context injected by context loaders (e.g. project files, docs).

Notification

Out-of-band side-channel signal injected mid-conversation: background-task completions, environment changes, system reminders. Adapters render it as a user-role message wrapped in <system-reminder> so the model interprets it as a notification rather than user input. Distinct from ItemKind::Context in two ways: (1) temporal placement is preserved (Anthropic adapter does NOT hoist it to the top-level system field), (2) UI hosts can filter or render notifications differently from user turns.

Use this when a tool runs in the background and its result arrives after the original tool_use was already paired and closed — emitting another tool_result for the same call_id would violate the provider schema.

Trait Implementations

impl Clone for ItemKind

fn clone(&self) -> ItemKind

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ItemKind

impl Debug for ItemKind

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ItemKind

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for ItemKind

impl Ord for ItemKind

fn cmp(&self, other: &ItemKind) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for ItemKind

fn eq(&self, other: &ItemKind) -> 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 PartialOrd for ItemKind

fn partial_cmp(&self, other: &ItemKind) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for ItemKind

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 ItemKind