Struct MessageContent 

pub struct MessageContent {
    pub role: String,
    pub content: Vec<ContentBlock>,
}

Message content wrapper

Contains role and content blocks for both user and assistant messages.

Example

{
  "role": "user",
  "content": [
    {"type": "text", "text": "Hello"},
    {"type": "tool_result", "tool_use_id": "...", "content": "..."}
  ]
}

Wire format drift

Real Claude Code transcripts (v2.1.2xx) put a bare JSON string in content for plain single-turn human prompts, not the documented array of content blocks — the array form is only used once the turn carries structured pieces (tool results, images, thinking). Both shapes are accepted: a bare string normalizes to a single ContentBlock::Text.

Fields

role: String

Role: “user” or “assistant”

content: Vec<ContentBlock>

Content blocks (text, tool use, tool results, etc.)

Accepts either the documented array-of-blocks shape or a bare string (the common shape for plain-text human prompts on disk).

Trait Implementations

impl Clone for MessageContent

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MessageContent

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for MessageContent

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for MessageContent

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

where __S: Serializer,

Serialize this value into the given Serde serializer.