Enum ProviderChunk 

pub enum ProviderChunk {
    MessageStart {
        id: String,
        model: String,
    },
    TextDelta {
        text: String,
    },
    ThinkingDelta {
        text: String,
    },
    ThinkingSignature {
        signature: String,
    },
    ToolUseStart {
        id: String,
        name: String,
    },
    ToolUseArgsDelta {
        id: String,
        fragment: String,
    },
    ToolUseEnd {
        id: String,
    },
    Stop {
        reason: StopReason,
    },
    Usage(Usage),
}

A single event produced by a provider’s streaming generation.

Semantic constraints:

• The first event of a stream is always ProviderChunk::MessageStart
• ProviderChunk::Stop is the last semantic event; only ProviderChunk::Usage may appear after it
• ProviderChunk::ToolUseArgsDelta chunks with the same tool_use_id are concatenated in arrival order to form the complete argument JSON; concurrent tool uses are accumulated per id, independent of wire order
• ProviderChunk::Usage may arrive multiple times; callers should accumulate each field

Variants

MessageStart

First event of the stream, containing only session-level metadata.

Fields

id: String

model: String

TextDelta

Incremental assistant text.

Fields

text: String

ThinkingDelta

Thinking-chain text delta (unified abstraction for Anthropic extended thinking, DeepSeek reasoning_content, o1-style reasoning, etc.).

Fields

text: String

ThinkingSignature

Thinking chain signature (Anthropic verification data for preserving thinking across multiple turns). Not text; should not be merged with ProviderChunk::ThinkingDelta.

Fields

signature: String

ToolUseStart

Tool call start: declares a new tool_use; subsequent ProviderChunk::ToolUseArgsDelta and ProviderChunk::ToolUseEnd are linked to this call via id.

Fields

id: String

name: String

ToolUseArgsDelta

A fragment of tool-use arguments.

fragment is a raw byte slice; it is not guaranteed to be a valid JSON substring. Callers must wait until the corresponding ProviderChunk::ToolUseEnd is received before parsing the complete payload as JSON.

Fields

id: String

fragment: String

ToolUseEnd

Tool call end: all ArgsDelta for this id have been sent.

Fields

id: String

Stop

The generation has ended.

Fields

reason: StopReason

Usage(Usage)

Token usage statistics. May arrive multiple times in a single stream; callers should accumulate rather than overwrite.

Trait Implementations

impl Clone for ProviderChunk

fn clone(&self) -> ProviderChunk

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ProviderChunk

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ProviderChunk

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for ProviderChunk

impl PartialEq for ProviderChunk

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

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 ProviderChunk