core intermediate

Demand Tracker Agent

A Jido agent that tracks listing demand with boost/cool/decay actions. Demonstrates Directives — the agent's mechanism for requesting side effects like emitting domain events (Emit) and scheduling future signals (Schedule).

directives emit schedule signals state

Related guides and notebooks

Guide

Your first agent

Define typed state and run your first command.

Livebook

Your first agent

Run the companion notebook in Livebook

Concept

Actions

Understand action contracts, validation, and composition.

Build your first workflow

Chain actions into a multi-step workflow.

Livebook

Build your first workflow

Run the companion notebook in Livebook

Explanation

What this example teaches

Interactive Demo

Run the agent and inspect state

Source Code

Read the production implementation

demand_tracker_agent.ex boost_action.ex cool_action.ex decay_action.ex toggle_auto_decay_action.ex demand_tracker_agent_live.ex

lib/agent_jido/demos/demand/actions/cool_action.ex 39 lines

defmodule AgentJido.Demos.Demand.CoolAction do
  @moduledoc """
  Decreases demand by a specified amount.
  Emits a domain event via the Emit directive.
  """
  use Jido.Action,
    name: "cool",
    description: "Cools listing demand",
    schema: [
      amount: [type: :integer, default: 10, doc: "Amount to cool demand by"]
    ]

  alias Jido.Agent.Directive
  alias Jido.Signal

  @impl true
  def run(%{amount: amount}, context) do
    current_demand = Map.get(context.state, :demand, 50)
    listing_id = Map.get(context.state, :listing_id, "demo-listing")
    new_demand = max(current_demand - amount, 0)
    now = DateTime.utc_now()

    emit_signal =
      Signal.new!(
        "listing.demand.changed",
        %{
          listing_id: listing_id,
          previous: current_demand,
          current: new_demand,
          delta: -amount,
          reason: :cool
        },
        source: "/demo/demand-tracker"
      )

    {:ok, %{demand: new_demand, last_updated_at: now}, Directive.emit(emit_signal)}
  end
end