opal

defmodule Opal.Tool.UseSkill do
  @moduledoc """
  Loads an agent skill's full instructions into the active context.

  Skills use progressive disclosure: only name/description are visible
  initially. This tool loads the full instructions when the agent decides
  a skill is relevant to the current task.
  """

  @behaviour Opal.Tool

  @impl true
  def name, do: "use_skill"

  @impl true
  def description do
    """
    Load a skill's full instructions into your context. Use this when you
    encounter a task that matches an available skill's description. The
    skill's detailed instructions will be added to your working context.
    """
  end

  @impl true
  def meta(%{"skill_name" => name}), do: "Loading skill: #{name}"
  def meta(_), do: "Loading skill"

  @impl true
  def parameters do
    %{
      "type" => "object",
      "properties" => %{
        "skill_name" => %{
          "type" => "string",
          "description" => "Name of the skill to load (from available skills list)."
        }
      },
      "required" => ["skill_name"]
    }
  end

  @impl true
  def execute(%{"skill_name" => skill_name}, %{agent_pid: agent_pid}) do
    case Opal.Agent.load_skill(agent_pid, skill_name) do
      {:ok, name} ->
        {:ok, "Skill '#{name}' loaded. Its instructions are now in your context."}

      {:already_loaded, name} ->
        {:ok, "Skill '#{name}' is already loaded."}

      {:error, reason} ->
        {:error, reason}
    end
  end

  def execute(%{"skill_name" => _}, _), do: {:error, "Missing agent_pid in context."}
  def execute(_, _), do: {:error, "Missing required parameter: skill_name"}
end