Struct TodoWriteOutcome 

pub struct TodoWriteOutcome {
    pub message: String,
    pub items: Vec<TodoItem>,
    pub diff: TodoDiff,
}

What todo_write returns to the dispatch layer.

The dispatch layer:

1. forwards message to the model as the tool result string;
2. when diff.is_empty() is false, emits crate::engine::EngineEvent::TodoUpdate with items and diff so every client sees the transition.

Splitting message (model-facing) from items + diff (client- facing) is the same separation Claude Code’s TodoWriteTool uses (mapToolResultToToolResultBlockParam returns a plain string while the structured diff goes to the UI). It keeps the model’s tool-result clean and the UI’s render data rich.

Fields

message: String

String returned to the model as the tool result.

items: Vec<TodoItem>

Full new list, after dedup short-circuit but always populated (even on the unchanged path) so callers that want to mirror the latest list don’t have to re-read from the DB.

diff: TodoDiff

Server-computed diff against the previously persisted list. is_empty() on the unchanged path; added is non-empty on the first write of a session.

Trait Implementations

impl Clone for TodoWriteOutcome

fn clone(&self) -> TodoWriteOutcome

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TodoWriteOutcome

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

Formats the value using the given formatter.