},

): Promise<AgentDeliveryPlan> {

const plan = resolveAgentDeliveryPlan(params);

if (

!params.wantsDelivery ||

!plan.resolvedTo ||

!isDeliverableMessageChannel(plan.resolvedChannel) ||

!resolveOutboundChannelPlugin({

channel: plan.resolvedChannel,

cfg: params.cfg,

allowBootstrap: true,

})?.messaging?.resolveOutboundSessionRoute

) {

const plugin =

params.wantsDelivery && plan.resolvedTo && isDeliverableMessageChannel(plan.resolvedChannel)

? resolveOutboundChannelPlugin({

channel: plan.resolvedChannel,

cfg: params.cfg,

allowBootstrap: true,

})

: undefined;

if (!plugin?.messaging?.resolveOutboundSessionRoute) {

return plan;

}

const plugin = resolveOutboundChannelPlugin({

channel: plan.resolvedChannel,

cfg: params.cfg,

allowBootstrap: true,

});

const normalizedTarget = resolveOutboundTarget({

channel: plan.resolvedChannel,

to: plan.resolvedTo,

candidates: match.entries,

};

}

// Directory miss: reject reserved literals before falling back to plugin

// resolution, so a bare reserved word without a matching directory entry

// does not accidentally resolve to a public channel or incorrect target.

// Directory misses are the fail-closed boundary for reserved literals.

if (reservedLiteral) {

return { ok: false, error: reservedTargetLiteralError(providerLabel, reservedLiteral, hint) };

}

return { ok: false, error: targetPrefixError };

}

const hint = plugin.messaging?.targetResolver?.hint;

// Reserved-literal rejection is skipped for heartbeat mode so the

// async directory-capable resolver (resolveChannelTarget →

// resolveMessagingTarget) can do directory-first lookup before deciding.

// Rejecting here would suppress a heartbeat route to an existing directory

// entry whose name matches a reserved literal.

// Heartbeats defer reserved literals to the async resolver so directory hits can win.

if (params.target.mode !== "heartbeat") {

const reservedLiteral = resolveReservedTargetLiteral({ raw: effectiveTo, plugin });

if (reservedLiteral) {