Struct SpecOutput 

#[non_exhaustive]
pub struct SpecOutput {
    pub name: String,
    pub media_type: Option<String>,
    pub framing: Framing,
    pub help: Option<String>,
    pub schema: Option<String>,
    pub default: bool,
    pub hide: bool,
    pub select: Option<String>,
}

One thing a command can write.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

name: String

The token a user types for it, e.g. human, json, ndjson.

media_type: Option<String>

The media type of the bytes, independent of their stream framing.

framing: Framing

The wire format, which is what a consumer keys off.

help: Option<String>

schema: Option<String>

A JSON Schema for what is written, carried verbatim.

Opaque on purpose: usage-lib has no runtime JSON dependency and is not going to grow one to hold a string it never inspects. Consumers that want it parsed — today that is only the MCP server — parse it themselves and fall back to the raw text, so a malformed schema degrades rather than failing a spec.

default: bool

What the command writes when nothing selects otherwise.

hide: bool

Declared in order to be taken away: a command that inherits a CLI-wide output it cannot produce redeclares the name with hide=#true. The same spelling as a hidden choice or alias.

select: Option<String>

A boolean flag whose presence picks this output, for the --json spelling.

Implementations

impl SpecOutput

pub fn new(name: impl Into<String>) -> Self

pub fn framing(self, framing: Framing) -> Self

pub fn media_type(self, media_type: impl Into<String>) -> Self

pub fn help(self, help: impl Into<String>) -> Self

pub fn schema(self, schema: impl Into<String>) -> Self

pub fn default_output(self) -> Self

pub fn select_argv(&self, cmd: &SpecCommand) -> Option<Selector>

How this output is asked for, given the command it belongs to.

None when no flag selects it. This is valid for an always-produced output; generated per-output SDK methods require a selector and therefore omit it.

Trait Implementations

impl Clone for SpecOutput

fn clone(&self) -> SpecOutput

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SpecOutput

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

Formats the value using the given formatter.

impl Default for SpecOutput

fn default() -> SpecOutput

Returns the “default value” for a type.

impl Serialize for SpecOutput

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

where __S: Serializer,

Serialize this value into the given Serde serializer.