Enum Feature 

pub enum Feature {
    SendMessage,
    SendStreamingMessage,
    GetTask,
    ListTasks,
    CancelTask,
    SubscribeToTask,
    PushNotificationConfig,
    GetExtendedAgentCard,
}

A capability an A2A peer can negotiate. Each variant has a row in tests::feature_matrix_golden that names the A2A spec section that introduced it.

Why a Copy newtype for the matrix

The matrix is a [[bool; N_FEATURES]; N_VERSIONS] — a per-revision row, indexed by Feature::ALL. The ALL array is the source of truth for the column count, so a new variant appended to the enum is the only edit the matrix needs to pick it up. The Copy derive keeps the Feature::ALL array a stack-local constant.

Variants

SendMessage

SendMessage — the unary message-send method.

SendStreamingMessage

SendStreamingMessage — the streaming counterpart of SendMessage, server-sent events on a Streamable HTTP POST.

GetTask

GetTask — fetch a task by id.

ListTasks

ListTasks — page through the tasks the agent owns.

CancelTask

CancelTask — request cancellation of an in-flight task.

SubscribeToTask

SubscribeToTask — long-poll or SSE-style subscription to task updates.

PushNotificationConfig

Push-notification config CRUD — the four Create*, Get*, List*, Delete* methods.

GetExtendedAgentCard

GetExtendedAgentCard — fetch the authenticated AgentCard once the peer has proven its identity.

Implementations

impl Feature

pub const ALL: [Self; 8]

Every variant, in declaration order. The matrix’s column order is this order; a variant appended here becomes a new column without a separate edit.

pub const fn label(&self) -> &'static str

The human-readable label used in the matrix snapshot and in the Display form. Kept here rather than derived so a future variant that needs a different label (e.g. for camelCase ↔ snake_case) can hold one without changing the matrix’s column header.

Trait Implementations

impl Clone for Feature

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Feature

impl Debug for Feature

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

Formats the value using the given formatter.

impl Eq for Feature

impl Hash for Feature

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Feature

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Feature