diff --git a/lib/microwaveprop_web/controllers/api_docs_controller.ex b/lib/microwaveprop_web/controllers/api_docs_controller.ex
new file mode 100644
index 00000000..79be6aa2
--- /dev/null
+++ b/lib/microwaveprop_web/controllers/api_docs_controller.ex
@@ -0,0 +1,35 @@
+defmodule MicrowavepropWeb.ApiDocsController do
+  @moduledoc """
+  Serves the static `docs/api/` artifacts:
+
+    * `GET /docs/api/openapi.yaml` — OpenAPI 3.1 spec as `application/yaml`.
+    * `GET /docs/api/README.md` — raw markdown source (for agents that
+      prefer markdown over the rendered LiveView page).
+
+  The human-facing rendered docs live at `/docs/api` via
+  `MicrowavepropWeb.ApiDocsLive`.
+  """
+  use MicrowavepropWeb, :controller
+
+  @external_resource "docs/api/openapi.yaml"
+  @external_resource "docs/api/README.md"
+
+  @openapi_yaml File.read!("docs/api/openapi.yaml")
+  @readme_markdown File.read!("docs/api/README.md")
+
+  @spec openapi_yaml(Plug.Conn.t(), map()) :: Plug.Conn.t()
+  def openapi_yaml(conn, _params) do
+    conn
+    |> put_resp_content_type("application/yaml", "utf-8")
+    |> put_resp_header("cache-control", "public, max-age=3600")
+    |> send_resp(200, @openapi_yaml)
+  end
+
+  @spec readme_markdown(Plug.Conn.t(), map()) :: Plug.Conn.t()
+  def readme_markdown(conn, _params) do
+    conn
+    |> put_resp_content_type("text/markdown", "utf-8")
+    |> put_resp_header("cache-control", "public, max-age=3600")
+    |> send_resp(200, @readme_markdown)
+  end
+end
diff --git a/lib/microwaveprop_web/live/api_docs_live.ex b/lib/microwaveprop_web/live/api_docs_live.ex
new file mode 100644
index 00000000..b8f19043
--- /dev/null
+++ b/lib/microwaveprop_web/live/api_docs_live.ex
@@ -0,0 +1,23 @@
+defmodule MicrowavepropWeb.ApiDocsLive do
+  @moduledoc "Renders `docs/api/README.md` as HTML at `/docs/api`."
+  use MicrowavepropWeb, :live_view
+
+  @external_resource "docs/api/README.md"
+  @docs_html "docs/api/README.md" |> File.read!() |> Microwaveprop.Markdown.to_html!()
+
+  @impl true
+  def mount(_params, _session, socket) do
+    {:ok, assign(socket, page_title: "API Documentation", content: @docs_html)}
+  end
+
+  @impl true
+  def render(assigns) do
+    ~H"""
+    <Layouts.app flash={@flash} current_scope={@current_scope}>
+      <div class="markdown-content">
+        {raw(@content)}
+      </div>
+    </Layouts.app>
+    """
+  end
+end
diff --git a/lib/microwaveprop_web/router.ex b/lib/microwaveprop_web/router.ex
index 777f736a..1f341ae3 100644
--- a/lib/microwaveprop_web/router.ex
+++ b/lib/microwaveprop_web/router.ex
@@ -212,7 +212,13 @@ defmodule MicrowavepropWeb.Router do
     get "/weather/cells", WeatherTileController, :cells
     get "/scores/cells", ScoresController, :cells
 
+    # Static API doc artifacts. Outside the live_session so the
+    # raw-format endpoints don't get the LiveView root layout.
+    get "/docs/api/openapi.yaml", ApiDocsController, :openapi_yaml
+    get "/docs/api/README.md", ApiDocsController, :readme_markdown
+
     live_session :public, on_mount: [{MicrowavepropWeb.UserAuth, :default}] do
+      live "/docs/api", ApiDocsLive
       live "/submit", SubmitLive
       live "/imports/:id", ImportLive
       live "/map", MapLive
diff --git a/test/microwaveprop_web/controllers/api_docs_controller_test.exs b/test/microwaveprop_web/controllers/api_docs_controller_test.exs
new file mode 100644
index 00000000..e6853118
--- /dev/null
+++ b/test/microwaveprop_web/controllers/api_docs_controller_test.exs
@@ -0,0 +1,22 @@
+defmodule MicrowavepropWeb.ApiDocsControllerTest do
+  use MicrowavepropWeb.ConnCase, async: true
+
+  describe "GET /docs/api/openapi.yaml" do
+    test "serves the OpenAPI spec as application/yaml", %{conn: conn} do
+      conn = get(conn, ~p"/docs/api/openapi.yaml")
+      assert conn.status == 200
+      assert get_resp_header(conn, "content-type") == ["application/yaml; charset=utf-8"]
+      assert conn.resp_body =~ "openapi: 3.1.0"
+      assert conn.resp_body =~ "/api/v1"
+    end
+  end
+
+  describe "GET /docs/api/README.md" do
+    test "serves the README markdown source", %{conn: conn} do
+      conn = get(conn, ~p"/docs/api/README.md")
+      assert conn.status == 200
+      assert get_resp_header(conn, "content-type") == ["text/markdown; charset=utf-8"]
+      assert conn.resp_body =~ "# Microwaveprop REST API"
+    end
+  end
+end
diff --git a/test/microwaveprop_web/live/api_docs_live_test.exs b/test/microwaveprop_web/live/api_docs_live_test.exs
new file mode 100644
index 00000000..00a28752
--- /dev/null
+++ b/test/microwaveprop_web/live/api_docs_live_test.exs
@@ -0,0 +1,13 @@
+defmodule MicrowavepropWeb.ApiDocsLiveTest do
+  use MicrowavepropWeb.ConnCase, async: true
+
+  import Phoenix.LiveViewTest
+
+  test "renders the API reference at /docs/api", %{conn: conn} do
+    {:ok, _view, html} = live(conn, ~p"/docs/api")
+
+    assert html =~ "Microwaveprop REST API"
+    assert html =~ "/api/v1"
+    assert html =~ "POST /auth/tokens"
+  end
+end