diff --git a/src/AMSlib/wf/action.hpp b/src/AMSlib/wf/action.hpp
new file mode 100644
index 00000000..6f875119
--- /dev/null
+++ b/src/AMSlib/wf/action.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "AMSError.hpp"
+
+namespace ams
+{
+
+struct EvalContext;  // forward declaration
+
+/// Base class for a single step in an AMS evaluation pipeline.
+///
+/// Actions mutate the shared EvalContext and may fail; failures are reported
+/// via AMSStatus so pipelines can short-circuit cleanly.
+class Action
+{
+public:
+  virtual ~Action() = default;
+
+  /// Execute this action on the evaluation context.
+  virtual AMSStatus run(EvalContext& ctx) = 0;
+
+  /// Human-readable name for debugging, logging, and tracing.
+  virtual const char* name() const noexcept = 0;
+};
+
+}  // namespace ams
diff --git a/src/AMSlib/wf/pipeline.hpp b/src/AMSlib/wf/pipeline.hpp
new file mode 100644
index 00000000..e412f0f0
--- /dev/null
+++ b/src/AMSlib/wf/pipeline.hpp
@@ -0,0 +1,55 @@
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include "AMSError.hpp"   // AMSStatus
+#include "wf/action.hpp"  // Action
+
+namespace ams
+{
+
+struct EvalContext;
+
+/// A linear sequence of Actions executed in order.
+///
+/// If any Action fails, execution stops and the error is returned.
+class Pipeline
+{
+public:
+  using ActionPtr = std::unique_ptr<Action>;
+
+  Pipeline() = default;
+
+  /// Append an Action to the pipeline.
+  Pipeline& add(ActionPtr Act)
+  {
+    Actions.emplace_back(std::move(Act));
+    return *this;
+  }
+
+  /// Execute all actions in order; stops on first error.
+  AMSStatus run(EvalContext& Ctx) const
+  {
+    for (const auto& Act : Actions) {
+      if (auto St = Act->run(Ctx); !St) {
+        return St;
+      }
+    }
+    return {};
+  }
+
+  /// Number of actions in the pipeline.
+  size_t size() const noexcept { return Actions.size(); }
+
+  /// True if there are no actions.
+  bool empty() const noexcept { return Actions.empty(); }
+
+  /// Remove all actions.
+  void clear() noexcept { Actions.clear(); }
+
+private:
+  std::vector<ActionPtr> Actions;
+};
+
+}  // namespace ams
diff --git a/tests/AMSlib/wf/CMakeLists.txt b/tests/AMSlib/wf/CMakeLists.txt
index 018b04b2..2c825b3c 100644
--- a/tests/AMSlib/wf/CMakeLists.txt
+++ b/tests/AMSlib/wf/CMakeLists.txt
@@ -56,3 +56,9 @@ ADD_WORKFLOW_UNIT_TEST(WORKFLOW::EVAL_CONTEXT eval_context)
 
 BUILD_UNIT_TEST(pointwise pointwise_layout_transform.cpp)
 ADD_WORKFLOW_UNIT_TEST(WORKFLOW::POINTWISE pointwise)
+
+BUILD_UNIT_TEST(action action.cpp)
+ADD_WORKFLOW_UNIT_TEST(WORKFLOW::ACTION action)
+
+BUILD_UNIT_TEST(pipeline pipeline.cpp)
+ADD_WORKFLOW_UNIT_TEST(WORKFLOW::PIPELINE pipeline)
diff --git a/tests/AMSlib/wf/action.cpp b/tests/AMSlib/wf/action.cpp
new file mode 100644
index 00000000..746cc18a
--- /dev/null
+++ b/tests/AMSlib/wf/action.cpp
@@ -0,0 +1,50 @@
+#include "wf/action.hpp"
+
+#include <catch2/catch_test_macros.hpp>
+#include <memory>
+#include <type_traits>
+
+// Prefer the real EvalContext if available.
+// If your project uses a different header name, adjust accordingly.
+#include "wf/eval_context.hpp"
+
+namespace ams
+{
+
+namespace
+{
+class TestAction final : public Action
+{
+public:
+  const char* name() const noexcept override { return "TestAction"; }
+
+  AMSStatus run(EvalContext& ctx) override
+  {
+    ctx.Threshold = ctx.Threshold.value_or(0.0f) + 1.0f;
+    return {};
+  }
+};
+}  // namespace
+
+CATCH_TEST_CASE("Action: abstract base class + virtual interface",
+                "[wf][action]")
+{
+  CATCH_STATIC_REQUIRE(std::is_abstract_v<Action>);
+  CATCH_STATIC_REQUIRE(std::has_virtual_destructor_v<Action>);
+
+  EvalContext ctx{};
+  ctx.Threshold = 0.0f;
+  std::unique_ptr<Action> act = std::make_unique<TestAction>();
+
+  CATCH_REQUIRE(act->name() == std::string("TestAction"));
+
+  auto Err = act->run(ctx);
+  CATCH_REQUIRE(Err);
+  CATCH_REQUIRE(ctx.Threshold == 1.0f);
+
+  auto Err1 = act->run(ctx);
+  CATCH_REQUIRE(Err1);
+  CATCH_REQUIRE(ctx.Threshold == 2.0f);
+}
+
+}  // namespace ams
diff --git a/tests/AMSlib/wf/pipeline.cpp b/tests/AMSlib/wf/pipeline.cpp
new file mode 100644
index 00000000..c02bf26c
--- /dev/null
+++ b/tests/AMSlib/wf/pipeline.cpp
@@ -0,0 +1,75 @@
+#include "wf/pipeline.hpp"
+
+#include <catch2/catch_test_macros.hpp>
+#include <memory>
+#include <string>
+
+#include "wf/eval_context.hpp"
+
+namespace ams
+{
+
+namespace
+{
+
+class IncAction final : public Action
+{
+public:
+  const char* name() const noexcept override { return "IncAction"; }
+
+  AMSStatus run(EvalContext& ctx) override
+  {
+    ctx.Threshold = ctx.Threshold.value_or(0.0f) + 1.0f;
+    return {};
+  }
+};
+
+class FailAction final : public Action
+{
+public:
+  const char* name() const noexcept override { return "FailAction"; }
+
+  AMSStatus run(EvalContext&) override
+  {
+    return AMS_MAKE_ERROR(AMSErrorType::Generic, "FailAction triggered");
+  }
+};
+
+}  // namespace
+
+CATCH_TEST_CASE("Pipeline runs actions in order and short-circuits on error",
+                "[wf][pipeline]")
+{
+  EvalContext Ctx{};
+  Pipeline P;
+
+  // Two increments -> Threshold becomes 2, then FailAction stops the pipeline.
+  P.add(std::make_unique<IncAction>())
+      .add(std::make_unique<IncAction>())
+      .add(std::make_unique<FailAction>())
+      .add(std::make_unique<IncAction>());  // must NOT execute
+
+  Ctx.Threshold = 0.0f;
+
+  auto St = P.run(Ctx);
+  CATCH_REQUIRE_FALSE(St);
+  CATCH_REQUIRE(St.error().getType() == AMSErrorType::Generic);
+
+  // Only the first two IncAction should have run.
+  CATCH_REQUIRE(Ctx.Threshold.value() == 2.0f);
+}
+
+CATCH_TEST_CASE("Pipeline succeeds when all actions succeed", "[wf][pipeline]")
+{
+  EvalContext Ctx{};
+  Pipeline P;
+
+  P.add(std::make_unique<IncAction>()).add(std::make_unique<IncAction>());
+
+  Ctx.Threshold = 0.0f;
+  auto St = P.run(Ctx);
+  CATCH_REQUIRE(St);
+  CATCH_REQUIRE(Ctx.Threshold.value() == 2.0f);
+}
+
+}  // namespace ams