Struct ToolOutput 

pub struct ToolOutput {
    pub text: String,
    pub original_tokens: usize,
    pub saved_tokens: usize,
    pub mode: Option<String>,
    pub path: Option<String>,
    pub changed: bool,
    pub shell_outcome: Option<ShellOutcome>,
    pub content_blocks: Option<Vec<ContentBlock>>,
}

Result returned by an McpTool handler.

Fields

text: String

original_tokens: usize

saved_tokens: usize

mode: Option<String>

path: Option<String>

Path associated with the tool call (for record_call_with_path).

changed: bool

True when the tool mutated state that clients should know about (e.g. dynamic tool categories changed).

shell_outcome: Option<ShellOutcome>

Set by shell-executing tools so dispatch can populate isError + structuredContent on the MCP result (GitHub #389). None for tools that don’t run shell commands.

content_blocks: Option<Vec<ContentBlock>>

Override content blocks for non-text responses (e.g. images). When set, dispatch uses these instead of wrapping text in TextContent.

Implementations

impl ToolOutput

pub fn simple(text: String) -> Self

pub fn to_header_line(&self, tool_name: &str) -> String

Compact one-line summary for headers_only response verbosity.

pub fn with_savings(text: String, original: usize, saved: usize) -> Self

pub fn image(blocks: Vec<ContentBlock>, path: String) -> Self

Construct a ToolOutput for image/binary content blocks. Bypasses all text processing in the dispatch pipeline.