Native extension point for router evidence providers.

An Adapter receives a projected, read-only routing request and returns scored references to rules that were visible to it. Spectre resolves those references against the compiled Definition, builds authoritative candidates, and leaves the final decision to the configured arbitrator.

defmodule MyApp.BinaryRouter do
  use Spectre.Router.Adapter,
    id: :binary,
    accept: 0.86,
    margin: 0.04,
    strength: :medium

  @impl Spectre.Router.Adapter
  def evaluate(%Spectre.Router.Adapter.Request{text: text, rules: rules}) do
    results =
      rules
      |> Enum.map(&result(&1, score(text, &1)))
      |> Enum.sort_by(& &1.score, :desc)
      |> Enum.take(32)

    {:ok, results}
  end
end

Adapters return evidence only. They cannot provide handlers, owners, terminal routes, acceptance decisions, or executable callbacks. They must rank or filter evidence to at most 32 distinct rule references; the core rejects an oversized response rather than silently choosing evidence for the Adapter.