# `ConduitMcp.Client.Policy.Decision`
[🔗](https://github.com/nyo16/conduit_mcp/blob/v0.11.0/lib/conduit_mcp/client/policy/decision.ex#L1)

The outcome of `ConduitMcp.Client.Policy.evaluate/4` (and its resource and
prompt variants).

  * `:decision` - `:allow`, `:ask` (run the approver) or `:deny`.
  * `:source` - what produced it: a `:deny`, `:ask` or `:allow` rule, the
    fingerprint pin (`:pin`), or the `:default`.
  * `:rule_id` - the matching rule's id (`{list, index}` such as
    `{:deny, 0}`, or the id given with `{:rule, id, pattern}`); `nil` for
    `:pin` and `:default`. When several rules in the deciding list match,
    it is the first in list order.
  * `:reason` - a closed atom (safe for telemetry and logs):
    * `:deny_rule`, `:ask_rule`, `:allow_rule` - a rule of that list
      matched;
    * `:predicate_failed` - a deny or ask rule's function or argument
      predicate raised, exited, threw or returned a non-boolean, and the
      rule was taken as matching (fail closed);
    * `:no_approver` - an ask rule matched but no approver exists, so the
      decision is `:deny`;
    * `:definition_changed` - the tool's fingerprint differs from the one
      it was approved with (`source: :pin`);
    * `:no_rule` - nothing matched (`source: :default`);
    * `:out_of_scope` - the policy's `:scope` does not cover this kind of
      target, so it does not govern it (`decision: :allow`,
      `source: :default`).

# `decision`

```elixir
@type decision() :: :allow | :ask | :deny
```

# `reason`

```elixir
@type reason() ::
  :deny_rule
  | :ask_rule
  | :allow_rule
  | :predicate_failed
  | :no_approver
  | :definition_changed
  | :no_rule
  | :out_of_scope
```

# `source`

```elixir
@type source() :: :deny | :ask | :allow | :default | :pin
```

# `t`

```elixir
@type t() :: %ConduitMcp.Client.Policy.Decision{
  decision: decision(),
  reason: reason(),
  rule_id: term(),
  source: source()
}
```

---

*Consult [api-reference.md](api-reference.md) for complete listing*