Struct AssistantMessage 

pub struct AssistantMessage {

    pub message: AssistantMessageContent,
    pub session_id: String,
    pub uuid: Option<String>,
    pub parent_tool_use_id: Option<String>,
    pub request_id: Option<String>,
    pub user_message_uuid: Option<String>,
    pub user_message_uuids: Vec<String>,
    pub subagent_type: Option<String>,
    pub task_description: Option<String>,
    pub error: Option<AssistantErrorKind>,
    pub aborted: Option<bool>,
    pub resumed_from_incomplete_thinking: Option<bool>,
    pub supersedes: Vec<String>,
    pub timestamp: Option<String>,
    pub tool_use_meta: Vec<ToolUseMeta>,
    pub batch_tool_uses: Vec<BatchToolUse>,
    pub wire_tool_inputs: Option<Map<String, Value>>,
    pub local_command_source: Option<String>,
    pub narration_block_indexes: Vec<usize>,
    pub context_usage: Option<ContextUsage>,
    pub is_meta: Option<bool>,
    pub is_virtual: Option<bool>,
    pub is_api_error_message: Option<bool>,
    pub api_error_status: Option<u16>,
    pub api_error: Option<String>,
    pub error_details: Option<String>,
    pub advisor_model: Option<String>,
    pub attribution_agent: Option<String>,
    pub attribution_skill: Option<String>,
    pub attribution_plugin: Option<String>,
    pub attribution_mcp_server: Option<String>,
    pub attribution_mcp_tool: Option<String>,
}

Assistant message

Fields

message: AssistantMessageContent

session_id: String

uuid: Option<String>

parent_tool_use_id: Option<String>

request_id: Option<String>

Anthropic API request id that produced this message (e.g. req_...).

user_message_uuid: Option<String>

Client uuid of the user message that triggered this turn, stamped on the turn’s first reply frame only so a consumer can bind the reply to the send it answers without waiting for the result. Absent on every later frame of the turn, on subagent frames, on synthetic/scheduled (meta) turns, and from CLIs before 2.1.259.

user_message_uuids: Vec<String>

Client uuids of every user message whose prompt this turn has consumed so far, in consumption order — all members of a prompt batch the host merged into this one turn. Always contains user_message_uuid; at most 64 entries. Present exactly when user_message_uuid is; absent from CLIs before 2.1.259 (fall back to user_message_uuid).

subagent_type: Option<String>

Subagent type, when this assistant message was produced inside a local_agent subagent (e.g. general-purpose, Explore).

task_description: Option<String>

Short description of the subagent task, present alongside subagent_type.

error: Option<AssistantErrorKind>

aborted: Option<bool>

True when this message was truncated by an interrupt/abort before the stream completed — stop_reason was never received and the content may end mid-word. Absent on normally completed messages.

resumed_from_incomplete_thinking: Option<bool>

True when this turn continued the preceding truncated assistant turn inside its trailing signed thinking block (max-output-tokens recovery). Histories replayed through the bridge must carry the flag back so the normalizer keeps the run’s prefix on the wire.

supersedes: Vec<String>

timestamp: Option<String>

tool_use_meta: Vec<ToolUseMeta>

batch_tool_uses: Vec<BatchToolUse>

{id, name} of the original Batch* tool_use block(s) for a message whose content was decomposed into synthetic v1 tool_use blocks. Round-tripped so a replayed history reassembles the batch block on the wire. Wrapper-level sibling — never inside message.content.

wire_tool_inputs: Option<Map<String, Value>>

tool_use.input exactly as the API produced it, keyed by tool_use id, for a message whose message.content carries the client-normalized input. Round-tripped so a replayed history echoes each earlier tool call back to the API as the API emitted it. Wrapper-level sibling — never inside message.content (CLI 2.1.259+).

local_command_source: Option<String>

The originating system/local_command row’s wire-form content, carried on the loop-synthesized local-command twin so a bridge/SDK history replay rebuilds the internal system row instead of dropping the output. Wrapper-level sibling — never inside message.content (CLI 2.1.259+).

narration_block_indexes: Vec<usize>

Ascending zero-based indexes into message.content of the thinking blocks whose signature the server tagged as narration (server summaries of the prose between tool calls, not the model’s own reasoning), so a renderer can label them as summaries without decoding the signature envelope. Fail-closed: an unparseable or legacy signature is not listed. Omitted when the frame has no such block and by CLIs before 2.1.260; treat unlisted thinking blocks as ordinary thinking. Wrapper-level sibling — never inside message.content.

context_usage: Option<ContextUsage>

Structured twin of the /context report, carried on the synthetic assistant message that delivers the markdown table. Present only on /context results from CLIs new enough to attach it (2.1.239+).

is_meta: Option<bool>

is_virtual: Option<bool>

is_api_error_message: Option<bool>

api_error_status: Option<u16>

api_error: Option<String>

error_details: Option<String>

advisor_model: Option<String>

attribution_agent: Option<String>

attribution_skill: Option<String>

attribution_plugin: Option<String>

attribution_mcp_server: Option<String>

attribution_mcp_tool: Option<String>

Trait Implementations

impl Clone for AssistantMessage

fn clone(&self) -> AssistantMessage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AssistantMessage

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AssistantMessage

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for AssistantMessage

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.