Struct Permissions 

pub struct Permissions;

The K9 unified evaluator. Rules + Mode + Hooks compose into a single Decision; deny-first; ask falls through to mode.

Stateless type — every input is a parameter. The active rules list is held in the process-wide active_permission_rules registry so callsites in mcp.rs / handlers.rs don’t need to thread a config handle through every function.

Implementations

impl Permissions

pub fn evaluate( ctx: &PermissionContext, hook_decisions: &[HookDecision], ) -> Decision

Evaluate the full pipeline.

hook_decisions is the (possibly empty) sequence of decisions returned by hook chains for this op. Callers that have not yet wired a hook chain into a particular op pass &[]; the pipeline still works (rules + mode resolve the decision).

pub fn evaluate_with( ctx: &PermissionContext, hook_decisions: &[HookDecision], rules: &[PermissionRule], mode: PermissionsMode, ) -> Decision

Same as Permissions::evaluate but takes the rule list and mode as explicit parameters. Used by the K9 test matrix so scenarios can exercise specific rule-set / mode combinations without poking the process-wide registry.

H8 invariant — namespace cannot be elevated by Modify

The pinned namespace for rule evaluation is taken from ctx.namespace BEFORE any rule pass. If a hook returns Modify { namespace: <other_ns> } the pipeline RE-EVALUATES the entire rule set against the new namespace; if that re-evaluation returns Decision::Deny, the modification is rejected (the original Deny reason is surfaced — annotated with the rejected escalation). This closes the v0.7.0 review blocker H8 / #628 where a Modify-rewrite of namespace could bypass a rule that targeted the destination namespace.