Struct DecisionMode 

pub struct DecisionMode { /* private fields */ }

Implementations

impl DecisionMode

pub fn new(evaluator: Arc<dyn PolicyEvaluator>) -> Self

Construct the mode with an injected governance policy evaluator.

Trait Implementations

impl Mode for DecisionMode

fn authorize_sender( &self, session: &Session, env: &Envelope, ) -> Result<(), MacpError>

Authorize the sender for decision mode messages.

Authority matrix (RFC-MACP-0004):

• Proposal, Evaluation, Objection, Vote → declared participant only
• Commitment → initiator or policy-delegated role

fn on_session_start( &self, _session: &Session, _env: &Envelope, ) -> Result<ModeResponse, MacpError>

Decision accepts an empty participants list.

RFC-MACP-0001 §7.1 requires participants only “when required by the Mode”, and RFC-MACP-0007 makes the initiator’s authority role-based rather than membership-based, so the roster and the authority model are independent here. A zero-participant Decision session is well-defined and inert: Self::authorize_sender routes Proposal, Evaluation, Objection and Vote through is_declared_participant, which is false over an empty list, so every such message is FORBIDDEN — the initiator’s included — and the session can only expire or be cancelled. Spec #99 removed minItems: 1 from the conformance fixture schema on that reasoning and added decision_zero_participants.json.

The roster rule is enforced in macp_core::session rather than here, so the carve-out is named in exactly one place and every other mode keeps the full canonical contract by default. The other four standards-track modes still re-reject an insufficient roster in their own on_session_start, which is where their mode-specific minima (Task’s “someone other than the initiator”, Handoff’s two parties) have to live anyway.

fn on_message( &self, session: &Session, env: &Envelope, ) -> Result<ModeResponse, MacpError>

fn on_message_at( &self, session: &Session, env: &Envelope, ctx: &MessageContext, ) -> Result<ModeResponse, MacpError>

Kernel entry point: on_message plus the runtime’s macp_core::mode::MessageContext (acceptance clock). Defaulted to plain on_message so most modes ignore it; modes that need a trustworthy time source (Handoff) override this instead of reading the forgeable Envelope.timestamp_unix_ms. The runtime and replay always call this, with the same clock value that the log entry records.