diff --git a/lib/towerops_web/controllers/api_docs_html/index.html.heex b/lib/towerops_web/controllers/api_docs_html/index.html.heex
index e4ce3382..5ec51b0d 100644
--- a/lib/towerops_web/controllers/api_docs_html/index.html.heex
+++ b/lib/towerops_web/controllers/api_docs_html/index.html.heex
@@ -76,6 +76,78 @@
                 Account Data (GDPR)
               </a>
             </li>
+            <li>
+              <a
+                href="#alerts"
+                data-nav-link="alerts"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Alerts
+              </a>
+            </li>
+            <li>
+              <a
+                href="#agents"
+                data-nav-link="agents"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Agents
+              </a>
+            </li>
+            <li>
+              <a
+                href="#organization"
+                data-nav-link="organization"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Organization
+              </a>
+            </li>
+            <li>
+              <a
+                href="#members"
+                data-nav-link="members"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Members
+              </a>
+            </li>
+            <li>
+              <a
+                href="#invitations"
+                data-nav-link="invitations"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Invitations
+              </a>
+            </li>
+            <li>
+              <a
+                href="#integrations"
+                data-nav-link="integrations"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Integrations
+              </a>
+            </li>
+            <li>
+              <a
+                href="#check-results"
+                data-nav-link="check-results"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Check Results & Metrics
+              </a>
+            </li>
+            <li>
+              <a
+                href="#activity"
+                data-nav-link="activity"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Activity Feed
+              </a>
+            </li>
             <li>
               <a
                 href="#graphs"
diff --git a/lib/towerops_web/graphql/resolvers/alert.ex b/lib/towerops_web/graphql/resolvers/alert.ex
new file mode 100644
index 00000000..98f2c007
--- /dev/null
+++ b/lib/towerops_web/graphql/resolvers/alert.ex
@@ -0,0 +1,77 @@
+defmodule ToweropsWeb.GraphQL.Resolvers.Alert do
+  @moduledoc "GraphQL resolvers for alert queries and mutations."
+
+  alias Towerops.Alerts
+  alias Towerops.Repo
+
+  def list(_parent, args, %{context: %{organization_id: org_id}}) do
+    filters =
+      args
+      |> Map.take([:status, :device_id, :limit])
+      |> Map.new(fn {k, v} -> {to_string(k), v} end)
+
+    alerts = Alerts.list_organization_alerts(org_id, filters)
+    {:ok, alerts}
+  end
+
+  def list(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def get(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    alert = Alerts.get_alert!(id)
+    device = alert.device
+
+    if device && device.organization_id == org_id do
+      {:ok, alert}
+    else
+      {:error, "Alert not found"}
+    end
+  rescue
+    Ecto.NoResultsError -> {:error, "Alert not found"}
+  end
+
+  def get(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def acknowledge(_parent, %{id: id}, %{context: %{organization_id: org_id} = ctx}) do
+    alert = Alerts.get_alert!(id)
+    device = alert.device
+
+    if device && device.organization_id == org_id do
+      user_id = ctx[:user] && ctx[:user].id
+
+      case Alerts.acknowledge_alert(alert, user_id) do
+        {:ok, updated} ->
+          {:ok, Repo.preload(updated, [:device, :acknowledged_by], force: true)}
+
+        {:error, _changeset} ->
+          {:error, "Could not acknowledge alert"}
+      end
+    else
+      {:error, "Alert not found"}
+    end
+  rescue
+    Ecto.NoResultsError -> {:error, "Alert not found"}
+  end
+
+  def acknowledge(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def resolve_alert(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    alert = Alerts.get_alert!(id)
+    device = alert.device
+
+    if device && device.organization_id == org_id do
+      case Alerts.resolve_alert(alert) do
+        {:ok, updated} ->
+          {:ok, Repo.preload(updated, [:device, :acknowledged_by], force: true)}
+
+        {:error, _changeset} ->
+          {:error, "Could not resolve alert"}
+      end
+    else
+      {:error, "Alert not found"}
+    end
+  rescue
+    Ecto.NoResultsError -> {:error, "Alert not found"}
+  end
+
+  def resolve_alert(_parent, _args, _resolution), do: {:error, "Authentication required"}
+end
diff --git a/lib/towerops_web/graphql/resolvers/device.ex b/lib/towerops_web/graphql/resolvers/device.ex
new file mode 100644
index 00000000..ba49ce02
--- /dev/null
+++ b/lib/towerops_web/graphql/resolvers/device.ex
@@ -0,0 +1,167 @@
+defmodule ToweropsWeb.GraphQL.Resolvers.Device do
+  @moduledoc "GraphQL resolvers for device queries and mutations."
+
+  alias Towerops.Devices
+  alias Towerops.Monitoring
+  alias Towerops.Repo
+  alias Towerops.Snmp
+
+  def list(_parent, args, %{context: %{organization_id: org_id}}) do
+    params = args |> Map.new(fn {k, v} -> {to_string(k), v} end)
+    devices = Devices.list_organization_devices(org_id, params)
+    {:ok, devices}
+  end
+
+  def list(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def get(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Devices.Device, id) do
+      nil ->
+        {:error, "Device not found"}
+
+      device ->
+        if device.organization_id == org_id do
+          {:ok, Repo.preload(device, :site)}
+        else
+          {:error, "Device not found"}
+        end
+    end
+  end
+
+  def get(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def create(_parent, %{input: input}, %{context: %{organization_id: org_id}}) do
+    attrs =
+      input
+      |> Map.new(fn {k, v} -> {to_string(k), v} end)
+      |> Map.put("organization_id", org_id)
+
+    case Devices.create_device(attrs) do
+      {:ok, device} -> {:ok, Repo.preload(device, :site)}
+      {:error, changeset} -> {:error, format_errors(changeset)}
+    end
+  end
+
+  def create(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def update(_parent, %{id: id, input: input}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Devices.Device, id) do
+      nil ->
+        {:error, "Device not found"}
+
+      device ->
+        if device.organization_id == org_id do
+          attrs = Map.new(input, fn {k, v} -> {to_string(k), v} end)
+
+          case Devices.update_device(device, attrs) do
+            {:ok, updated} -> {:ok, Repo.preload(updated, :site, force: true)}
+            {:error, changeset} -> {:error, format_errors(changeset)}
+          end
+        else
+          {:error, "Device not found"}
+        end
+    end
+  end
+
+  def update(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def delete(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Devices.Device, id) do
+      nil ->
+        {:error, "Device not found"}
+
+      device ->
+        if device.organization_id == org_id do
+          case Devices.delete_device(device) do
+            {:ok, _} -> {:ok, %{success: true, message: "Device deleted"}}
+            {:error, _} -> {:ok, %{success: false, message: "Could not delete device"}}
+          end
+        else
+          {:error, "Device not found"}
+        end
+    end
+  end
+
+  def delete(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def metrics(_parent, %{device_id: device_id} = args, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Devices.Device, device_id) do
+      nil ->
+        {:error, "Device not found"}
+
+      device ->
+        if device.organization_id == org_id do
+          hours = parse_time_range(Map.get(args, :time_range, "24h"))
+          from_time = DateTime.add(DateTime.utc_now(), -hours * 3600, :second)
+          check_type = args[:sensor_type]
+
+          checks = Monitoring.list_checks(org_id, device_id: device.id, check_type: check_type)
+
+          metrics =
+            Enum.flat_map(checks, fn check ->
+              results = Monitoring.get_check_results(check.id, from: from_time)
+
+              Enum.map(results, fn r ->
+                %{
+                  timestamp: to_string(r.checked_at),
+                  value: r.value,
+                  status: r.status,
+                  check_name: check.name,
+                  check_type: check.check_type
+                }
+              end)
+            end)
+
+          {:ok, metrics}
+        else
+          {:error, "Device not found"}
+        end
+    end
+  end
+
+  def metrics(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def interfaces(_parent, %{device_id: device_id}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Devices.Device, device_id) do
+      nil ->
+        {:error, "Device not found"}
+
+      device ->
+        if device.organization_id == org_id do
+          device = Repo.preload(device, :snmp_device)
+
+          interfaces =
+            case device.snmp_device do
+              nil ->
+                []
+
+              snmp_device ->
+                Snmp.list_interfaces(snmp_device.id)
+            end
+
+          {:ok, interfaces}
+        else
+          {:error, "Device not found"}
+        end
+    end
+  end
+
+  def interfaces(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  defp parse_time_range(range) do
+    case Integer.parse(String.replace(range, "h", "")) do
+      {hours, _} -> hours
+      :error -> 24
+    end
+  end
+
+  defp format_errors(changeset) do
+    Ecto.Changeset.traverse_errors(changeset, fn {msg, opts} ->
+      Regex.replace(~r"%{(\w+)}", msg, fn _, key ->
+        opts |> Keyword.get(String.to_existing_atom(key), key) |> to_string()
+      end)
+    end)
+    |> Enum.map(fn {field, messages} -> "#{field}: #{Enum.join(messages, ", ")}" end)
+    |> Enum.join("; ")
+  end
+end
diff --git a/lib/towerops_web/graphql/resolvers/site.ex b/lib/towerops_web/graphql/resolvers/site.ex
new file mode 100644
index 00000000..41e96e30
--- /dev/null
+++ b/lib/towerops_web/graphql/resolvers/site.ex
@@ -0,0 +1,87 @@
+defmodule ToweropsWeb.GraphQL.Resolvers.Site do
+  @moduledoc "GraphQL resolvers for site queries and mutations."
+
+  alias Towerops.Repo
+  alias Towerops.Sites
+
+  def list(_parent, _args, %{context: %{organization_id: org_id}}) do
+    sites = Sites.list_organization_sites(org_id)
+    {:ok, sites}
+  end
+
+  def list(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def get(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Sites.Site, id) do
+      nil -> {:error, "Site not found"}
+      site ->
+        if site.organization_id == org_id do
+          {:ok, site}
+        else
+          {:error, "Site not found"}
+        end
+    end
+  end
+
+  def get(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def create(_parent, %{input: input}, %{context: %{organization_id: org_id}}) do
+    attrs =
+      input
+      |> Map.new(fn {k, v} -> {to_string(k), v} end)
+      |> Map.put("organization_id", org_id)
+
+    case Sites.create_site(attrs) do
+      {:ok, site} -> {:ok, site}
+      {:error, changeset} -> {:error, format_errors(changeset)}
+    end
+  end
+
+  def create(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def update(_parent, %{id: id, input: input}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Sites.Site, id) do
+      nil -> {:error, "Site not found"}
+      site ->
+        if site.organization_id == org_id do
+          attrs = Map.new(input, fn {k, v} -> {to_string(k), v} end)
+
+          case Sites.update_site(site, attrs) do
+            {:ok, updated} -> {:ok, updated}
+            {:error, changeset} -> {:error, format_errors(changeset)}
+          end
+        else
+          {:error, "Site not found"}
+        end
+    end
+  end
+
+  def update(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  def delete(_parent, %{id: id}, %{context: %{organization_id: org_id}}) do
+    case Repo.get(Towerops.Sites.Site, id) do
+      nil -> {:error, "Site not found"}
+      site ->
+        if site.organization_id == org_id do
+          case Sites.delete_site(site) do
+            {:ok, _} -> {:ok, %{success: true, message: "Site deleted"}}
+            {:error, _} -> {:ok, %{success: false, message: "Could not delete site"}}
+          end
+        else
+          {:error, "Site not found"}
+        end
+    end
+  end
+
+  def delete(_parent, _args, _resolution), do: {:error, "Authentication required"}
+
+  defp format_errors(changeset) do
+    Ecto.Changeset.traverse_errors(changeset, fn {msg, opts} ->
+      Regex.replace(~r"%{(\w+)}", msg, fn _, key ->
+        opts |> Keyword.get(String.to_existing_atom(key), key) |> to_string()
+      end)
+    end)
+    |> Enum.map(fn {field, messages} -> "#{field}: #{Enum.join(messages, ", ")}" end)
+    |> Enum.join("; ")
+  end
+end
diff --git a/lib/towerops_web/graphql/schema.ex b/lib/towerops_web/graphql/schema.ex
new file mode 100644
index 00000000..70b7dad4
--- /dev/null
+++ b/lib/towerops_web/graphql/schema.ex
@@ -0,0 +1,212 @@
+defmodule ToweropsWeb.GraphQL.Schema do
+  @moduledoc """
+  GraphQL schema for the TowerOps API.
+
+  Provides a complete GraphQL interface for managing devices, sites, alerts,
+  agents, organization settings, members, integrations, and activity feeds.
+  """
+  use Absinthe.Schema
+
+  import_types ToweropsWeb.GraphQL.Types.Common
+  import_types ToweropsWeb.GraphQL.Types.Device
+  import_types ToweropsWeb.GraphQL.Types.Site
+  import_types ToweropsWeb.GraphQL.Types.Alert
+  import_types ToweropsWeb.GraphQL.Types.Agent
+  import_types ToweropsWeb.GraphQL.Types.Organization
+  import_types ToweropsWeb.GraphQL.Types.Member
+  import_types ToweropsWeb.GraphQL.Types.Integration
+  import_types ToweropsWeb.GraphQL.Types.Activity
+
+  query do
+    # Devices
+    field :devices, list_of(:device) do
+      arg :site_id, :id
+      arg :status, :string
+      arg :limit, :integer, default_value: 100
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.list/3
+    end
+
+    field :device, :device do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.get/3
+    end
+
+    # Sites
+    field :sites, list_of(:site) do
+      resolve &ToweropsWeb.GraphQL.Resolvers.Site.list/3
+    end
+
+    field :site, :site do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Site.get/3
+    end
+
+    # Alerts
+    field :alerts, list_of(:alert) do
+      arg :status, :string
+      arg :device_id, :id
+      arg :limit, :integer, default_value: 100
+      resolve &ToweropsWeb.GraphQL.Resolvers.Alert.list/3
+    end
+
+    field :alert, :alert do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Alert.get/3
+    end
+
+    # Agents
+    field :agents, list_of(:agent) do
+      resolve &ToweropsWeb.GraphQL.Resolvers.Agent.list/3
+    end
+
+    field :agent, :agent do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Agent.get/3
+    end
+
+    # Organization
+    field :organization, :organization do
+      resolve &ToweropsWeb.GraphQL.Resolvers.Organization.get/3
+    end
+
+    # Members
+    field :members, list_of(:member) do
+      resolve &ToweropsWeb.GraphQL.Resolvers.Member.list/3
+    end
+
+    # Integrations
+    field :integrations, list_of(:integration) do
+      resolve &ToweropsWeb.GraphQL.Resolvers.Integration.list/3
+    end
+
+    # Activity feed
+    field :activity, list_of(:activity_item) do
+      arg :limit, :integer, default_value: 50
+      arg :type, :string
+      resolve &ToweropsWeb.GraphQL.Resolvers.Activity.list/3
+    end
+
+    # Device metrics
+    field :device_metrics, list_of(:metric_point) do
+      arg :device_id, non_null(:id)
+      arg :sensor_type, :string
+      arg :time_range, :string, default_value: "24h"
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.metrics/3
+    end
+
+    # Device interfaces
+    field :device_interfaces, list_of(:interface) do
+      arg :device_id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.interfaces/3
+    end
+  end
+
+  mutation do
+    # Device CRUD
+    field :create_device, :device do
+      arg :input, non_null(:device_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.create/3
+    end
+
+    field :update_device, :device do
+      arg :id, non_null(:id)
+      arg :input, non_null(:device_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.update/3
+    end
+
+    field :delete_device, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Device.delete/3
+    end
+
+    # Site CRUD
+    field :create_site, :site do
+      arg :input, non_null(:site_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Site.create/3
+    end
+
+    field :update_site, :site do
+      arg :id, non_null(:id)
+      arg :input, non_null(:site_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Site.update/3
+    end
+
+    field :delete_site, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Site.delete/3
+    end
+
+    # Alert actions
+    field :acknowledge_alert, :alert do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Alert.acknowledge/3
+    end
+
+    field :resolve_alert, :alert do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Alert.resolve_alert/3
+    end
+
+    # Agent management
+    field :create_agent, :agent_with_token do
+      arg :name, non_null(:string)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Agent.create/3
+    end
+
+    field :delete_agent, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Agent.delete/3
+    end
+
+    # Organization settings
+    field :update_organization, :organization do
+      arg :input, non_null(:organization_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Organization.update/3
+    end
+
+    # Member management
+    field :send_invitation, :invitation do
+      arg :email, non_null(:string)
+      arg :role, :string, default_value: "member"
+      resolve &ToweropsWeb.GraphQL.Resolvers.Member.invite/3
+    end
+
+    field :cancel_invitation, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Member.cancel_invitation/3
+    end
+
+    field :remove_member, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Member.remove/3
+    end
+
+    field :update_member_role, :member do
+      arg :id, non_null(:id)
+      arg :role, non_null(:string)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Member.update_role/3
+    end
+
+    # Integrations
+    field :create_integration, :integration do
+      arg :input, non_null(:integration_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Integration.create/3
+    end
+
+    field :update_integration, :integration do
+      arg :id, non_null(:id)
+      arg :input, non_null(:integration_input)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Integration.update/3
+    end
+
+    field :delete_integration, :delete_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Integration.delete/3
+    end
+
+    field :test_integration, :test_result do
+      arg :id, non_null(:id)
+      resolve &ToweropsWeb.GraphQL.Resolvers.Integration.test_connection/3
+    end
+  end
+end
diff --git a/lib/towerops_web/graphql/types/activity.ex b/lib/towerops_web/graphql/types/activity.ex
new file mode 100644
index 00000000..b8f107d8
--- /dev/null
+++ b/lib/towerops_web/graphql/types/activity.ex
@@ -0,0 +1,16 @@
+defmodule ToweropsWeb.GraphQL.Types.Activity do
+  @moduledoc "GraphQL types for activity feed items."
+  use Absinthe.Schema.Notation
+
+  object :activity_item do
+    field :summary, :string
+    field :detail, :string
+    field :timestamp, :string
+    field :severity, :string
+    field :icon, :string
+    field :device_name, :string
+    field :site_name, :string
+    field :link, :string
+    field :type, :string
+  end
+end
diff --git a/lib/towerops_web/graphql/types/agent.ex b/lib/towerops_web/graphql/types/agent.ex
new file mode 100644
index 00000000..0fa00c16
--- /dev/null
+++ b/lib/towerops_web/graphql/types/agent.ex
@@ -0,0 +1,33 @@
+defmodule ToweropsWeb.GraphQL.Types.Agent do
+  @moduledoc "GraphQL types for agents."
+  use Absinthe.Schema.Notation
+
+  object :agent do
+    field :id, :id
+    field :name, :string
+    field :enabled, :boolean
+    field :is_cloud_poller, :boolean
+    field :allow_remote_debug, :boolean
+    field :last_seen_at, :string
+    field :last_ip, :string
+    field :metadata, :json
+    field :organization_id, :id
+    field :inserted_at, :string
+    field :updated_at, :string
+
+    field :device_count, :integer do
+      resolve fn agent, _, _ ->
+        count = Towerops.Agents.count_assigned_devices(agent.id)
+        {:ok, count}
+      end
+    end
+  end
+
+  object :agent_with_token do
+    field :id, :id
+    field :name, :string
+    field :enabled, :boolean
+    field :token, :string
+    field :inserted_at, :string
+  end
+end
diff --git a/lib/towerops_web/graphql/types/alert.ex b/lib/towerops_web/graphql/types/alert.ex
new file mode 100644
index 00000000..506aa741
--- /dev/null
+++ b/lib/towerops_web/graphql/types/alert.ex
@@ -0,0 +1,48 @@
+defmodule ToweropsWeb.GraphQL.Types.Alert do
+  @moduledoc "GraphQL types for alerts."
+  use Absinthe.Schema.Notation
+
+  object :alert do
+    field :id, :id
+    field :alert_type, :string
+    field :message, :string
+    field :triggered_at, :string
+    field :acknowledged_at, :string
+    field :resolved_at, :string
+    field :email_sent_at, :string
+    field :device_id, :id
+    field :acknowledged_by_id, :id
+    field :gaiia_impact, :json
+    field :inserted_at, :string
+
+    field :device, :device do
+      resolve fn alert, _, _ ->
+        case alert.device do
+          %Ecto.Association.NotLoaded{} -> {:ok, nil}
+          device -> {:ok, device}
+        end
+      end
+    end
+
+    field :acknowledged_by_email, :string do
+      resolve fn alert, _, _ ->
+        case alert.acknowledged_by do
+          %Ecto.Association.NotLoaded{} -> {:ok, nil}
+          nil -> {:ok, nil}
+          user -> {:ok, user.email}
+        end
+      end
+    end
+  end
+
+  scalar :json do
+    parse fn input ->
+      case Jason.decode(input.value) do
+        {:ok, result} -> {:ok, result}
+        _ -> :error
+      end
+    end
+
+    serialize fn value -> value end
+  end
+end
diff --git a/lib/towerops_web/graphql/types/common.ex b/lib/towerops_web/graphql/types/common.ex
new file mode 100644
index 00000000..98e774fa
--- /dev/null
+++ b/lib/towerops_web/graphql/types/common.ex
@@ -0,0 +1,34 @@
+defmodule ToweropsWeb.GraphQL.Types.Common do
+  @moduledoc "Common GraphQL types shared across the schema."
+  use Absinthe.Schema.Notation
+
+  object :delete_result do
+    field :success, non_null(:boolean)
+    field :message, :string
+  end
+
+  object :test_result do
+    field :success, non_null(:boolean)
+    field :message, :string
+  end
+
+  object :metric_point do
+    field :timestamp, :string
+    field :value, :float
+    field :status, :string
+    field :check_name, :string
+    field :check_type, :string
+  end
+
+  object :interface do
+    field :id, :id
+    field :if_index, :integer
+    field :if_name, :string
+    field :if_descr, :string
+    field :if_type, :string
+    field :if_speed, :float
+    field :if_admin_status, :string
+    field :if_oper_status, :string
+    field :if_alias, :string
+  end
+end
diff --git a/lib/towerops_web/graphql/types/device.ex b/lib/towerops_web/graphql/types/device.ex
new file mode 100644
index 00000000..2010ca7b
--- /dev/null
+++ b/lib/towerops_web/graphql/types/device.ex
@@ -0,0 +1,87 @@
+defmodule ToweropsWeb.GraphQL.Types.Device do
+  @moduledoc "GraphQL types for devices."
+  use Absinthe.Schema.Notation
+
+  object :device do
+    field :id, :id
+    field :name, :string
+    field :ip_address, :string
+    field :description, :string
+    field :display_order, :integer
+    field :status, :string
+    field :last_checked_at, :string
+    field :last_status_change_at, :string
+    field :monitoring_enabled, :boolean
+    field :check_interval_seconds, :integer
+
+    # SNMP fields
+    field :snmp_enabled, :boolean
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_community_source, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+    field :snmp_transport_source, :string
+    field :last_discovery_at, :string
+    field :last_snmp_poll_at, :string
+
+    # SNMPv3 fields
+    field :snmpv3_security_level, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_priv_protocol, :string
+    field :snmpv3_credential_source, :string
+
+    # MikroTik fields
+    field :mikrotik_username, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+    field :mikrotik_enabled, :boolean
+    field :mikrotik_credential_source, :string
+
+    # Topology
+    field :device_role, :string
+    field :device_role_source, :string
+
+    field :site_id, :id
+    field :organization_id, :id
+    field :inserted_at, :string
+    field :updated_at, :string
+
+    field :site, :site do
+      resolve fn device, _, _ ->
+        case device.site do
+          %Ecto.Association.NotLoaded{} -> {:ok, nil}
+          site -> {:ok, site}
+        end
+      end
+    end
+  end
+
+  input_object :device_input do
+    field :name, :string
+    field :ip_address, :string
+    field :description, :string
+    field :site_id, :id
+    field :monitoring_enabled, :boolean
+    field :check_interval_seconds, :integer
+    field :snmp_enabled, :boolean
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_auth_password, :string
+    field :snmpv3_priv_protocol, :string
+    field :snmpv3_priv_password, :string
+    field :mikrotik_username, :string
+    field :mikrotik_password, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+    field :mikrotik_enabled, :boolean
+    field :device_role, :string
+  end
+end
diff --git a/lib/towerops_web/graphql/types/integration.ex b/lib/towerops_web/graphql/types/integration.ex
new file mode 100644
index 00000000..36d3f915
--- /dev/null
+++ b/lib/towerops_web/graphql/types/integration.ex
@@ -0,0 +1,23 @@
+defmodule ToweropsWeb.GraphQL.Types.Integration do
+  @moduledoc "GraphQL types for integrations."
+  use Absinthe.Schema.Notation
+
+  object :integration do
+    field :id, :id
+    field :provider, :string
+    field :enabled, :boolean
+    field :sync_interval_minutes, :integer
+    field :last_synced_at, :string
+    field :last_sync_status, :string
+    field :organization_id, :id
+    field :inserted_at, :string
+    field :updated_at, :string
+  end
+
+  input_object :integration_input do
+    field :provider, :string
+    field :enabled, :boolean
+    field :credentials, :json
+    field :sync_interval_minutes, :integer
+  end
+end
diff --git a/lib/towerops_web/graphql/types/member.ex b/lib/towerops_web/graphql/types/member.ex
new file mode 100644
index 00000000..a089ab4b
--- /dev/null
+++ b/lib/towerops_web/graphql/types/member.ex
@@ -0,0 +1,31 @@
+defmodule ToweropsWeb.GraphQL.Types.Member do
+  @moduledoc "GraphQL types for members and invitations."
+  use Absinthe.Schema.Notation
+
+  object :member do
+    field :id, :id
+    field :role, :string
+    field :is_default, :boolean
+    field :inserted_at, :string
+
+    field :user_id, :id
+    field :email, :string do
+      resolve fn membership, _, _ ->
+        case membership.user do
+          %Ecto.Association.NotLoaded{} -> {:ok, nil}
+          nil -> {:ok, nil}
+          user -> {:ok, user.email}
+        end
+      end
+    end
+  end
+
+  object :invitation do
+    field :id, :id
+    field :email, :string
+    field :role, :string
+    field :expires_at, :string
+    field :accepted_at, :string
+    field :inserted_at, :string
+  end
+end
diff --git a/lib/towerops_web/graphql/types/organization.ex b/lib/towerops_web/graphql/types/organization.ex
new file mode 100644
index 00000000..29eed548
--- /dev/null
+++ b/lib/towerops_web/graphql/types/organization.ex
@@ -0,0 +1,56 @@
+defmodule ToweropsWeb.GraphQL.Types.Organization do
+  @moduledoc "GraphQL types for organizations."
+  use Absinthe.Schema.Notation
+
+  object :organization do
+    field :id, :id
+    field :name, :string
+    field :slug, :string
+    field :subscription_plan, :string
+    field :use_sites, :boolean
+
+    # SNMP defaults
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+
+    # SNMPv3 defaults
+    field :snmpv3_security_level, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_priv_protocol, :string
+
+    # MikroTik defaults
+    field :mikrotik_enabled, :boolean
+    field :mikrotik_username, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+
+    field :default_agent_token_id, :id
+    field :inserted_at, :string
+    field :updated_at, :string
+  end
+
+  input_object :organization_input do
+    field :name, :string
+    field :use_sites, :boolean
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_auth_password, :string
+    field :snmpv3_priv_protocol, :string
+    field :snmpv3_priv_password, :string
+    field :mikrotik_enabled, :boolean
+    field :mikrotik_username, :string
+    field :mikrotik_password, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+    field :default_agent_token_id, :id
+  end
+end
diff --git a/lib/towerops_web/graphql/types/site.ex b/lib/towerops_web/graphql/types/site.ex
new file mode 100644
index 00000000..82cb72e0
--- /dev/null
+++ b/lib/towerops_web/graphql/types/site.ex
@@ -0,0 +1,60 @@
+defmodule ToweropsWeb.GraphQL.Types.Site do
+  @moduledoc "GraphQL types for sites."
+  use Absinthe.Schema.Notation
+
+  object :site do
+    field :id, :id
+    field :name, :string
+    field :description, :string
+    field :location, :string
+    field :display_order, :integer
+
+    # SNMP config
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+
+    # SNMPv3
+    field :snmpv3_security_level, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_priv_protocol, :string
+
+    # MikroTik
+    field :mikrotik_username, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+    field :mikrotik_enabled, :boolean
+
+    field :organization_id, :id
+    field :agent_token_id, :id
+    field :parent_site_id, :id
+    field :inserted_at, :string
+    field :updated_at, :string
+  end
+
+  input_object :site_input do
+    field :name, :string
+    field :description, :string
+    field :location, :string
+    field :snmp_version, :string
+    field :snmp_community, :string
+    field :snmp_port, :integer
+    field :snmp_transport, :string
+    field :snmpv3_username, :string
+    field :snmpv3_auth_protocol, :string
+    field :snmpv3_auth_password, :string
+    field :snmpv3_priv_protocol, :string
+    field :snmpv3_priv_password, :string
+    field :mikrotik_username, :string
+    field :mikrotik_password, :string
+    field :mikrotik_port, :integer
+    field :mikrotik_ssh_port, :integer
+    field :mikrotik_use_ssl, :boolean
+    field :mikrotik_enabled, :boolean
+    field :agent_token_id, :id
+    field :parent_site_id, :id
+  end
+end
diff --git a/lib/towerops_web/live/org/settings_live.html.heex b/lib/towerops_web/live/org/settings_live.html.heex
index 774ffa86..8f0c067a 100644
--- a/lib/towerops_web/live/org/settings_live.html.heex
+++ b/lib/towerops_web/live/org/settings_live.html.heex
@@ -841,7 +841,12 @@
                           Syncs every {integration.sync_interval_minutes} minutes. Reconciliation runs nightly. Also receives real-time webhook updates.
                         <% end %>
                         <%= if provider.id == "pagerduty" do %>
-                          Event-driven — alerts are sent to PagerDuty in real time when devices go down, are acknowledged, or recover.
+                          Event-driven — no polling needed. TowerOps sends events to PagerDuty in real time:
+                          <ul class="mt-1 space-y-0.5 list-disc list-inside text-xs text-gray-500 dark:text-gray-400">
+                            <li><strong class="text-gray-700 dark:text-gray-300">Device down</strong> → PagerDuty incident triggered (critical)</li>
+                            <li><strong class="text-gray-700 dark:text-gray-300">Alert acknowledged</strong> → PagerDuty incident acknowledged</li>
+                            <li><strong class="text-gray-700 dark:text-gray-300">Device recovers</strong> → PagerDuty incident auto-resolved</li>
+                          </ul>
                         <% end %>
                       </p>
                     </div>
@@ -904,9 +909,20 @@
                 />
 
                 <%= if provider.id == "pagerduty" do %>
-                  <p class="text-xs text-gray-500 dark:text-gray-400 -mt-2">
-                    Find this in PagerDuty → Services → Your Service → Integrations → Events API v2
-                  </p>
+                  <div class="rounded-md bg-blue-50 dark:bg-blue-900/20 border border-blue-200 dark:border-blue-800 p-4 -mt-1">
+                    <h4 class="text-xs font-semibold text-blue-900 dark:text-blue-300 mb-2">
+                      Where to find your Integration Key
+                    </h4>
+                    <ol class="list-decimal list-inside space-y-1 text-xs text-blue-800 dark:text-blue-300">
+                      <li>In PagerDuty, go to <strong>Services</strong> → select your service (or create one)</li>
+                      <li>Click the <strong>Integrations</strong> tab</li>
+                      <li>Click <strong>Add Integration</strong> → select <strong>Events API v2</strong></li>
+                      <li>Copy the <strong>Integration Key</strong> and paste it above</li>
+                    </ol>
+                    <p class="mt-2 text-xs text-blue-700 dark:text-blue-400">
+                      When connected, TowerOps will automatically trigger, acknowledge, and resolve PagerDuty incidents in sync with your alerts.
+                    </p>
+                  </div>
                 <% end %>
 
                 <%= if provider.id != "pagerduty" do %>
diff --git a/mix.exs b/mix.exs
index 674efbc7..489cdc41 100644
--- a/mix.exs
+++ b/mix.exs
@@ -77,6 +77,8 @@ defmodule Towerops.MixProject do
       {:phoenix_pubsub_redis, "~> 3.0"},
       {:ecto_psql_extras, "~> 0.6"},
       {:mox, "~> 1.0", only: :test},
+      {:absinthe, "~> 1.7"},
+      {:absinthe_plug, "~> 1.5"},
       {:honeybadger, "~> 0.24"},
       {:stream_data, "~> 1.1", only: :test},
       {:tzdata, "~> 1.1"},