fix(actor): remove type: ignore from subgraph cycle detection steps

Remove # type: ignore[import-untyped] suppression comments from
features/steps/actor_subgraph_cycle_detection_steps.py per
CONTRIBUTING.md zero-tolerance policy on inline type suppressions.
Pyright does not check the features/ directory so these suppressions
were unnecessary and violated project policy.

CHANGELOG.md

@@ -5,6 +5,19 @@ The format follows [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ## [Unreleased]
 
+### Fixed
+
+- **Cross-actor subgraph cycle detection reads actor_ref field** (#1431): Fixed
+  `_detect_subgraph_cycles()`, `_map_node()`, and the `compile_actor()` main loop
+  in `src/cleveragents/actor/compiler.py` to read `actor_ref` from the top-level
+  `NodeDefinition.actor_ref` field instead of `node.config.get("actor_ref", "")`.
+  Because `actor_ref` is a typed, validated Pydantic field (not a key inside the
+  untyped `config` dict), the old code always returned an empty string, causing
+  cross-actor cycle detection to silently fail and leaving the system vulnerable to
+  infinite recursion at runtime. Added Behave regression tests
+  (`features/actor_subgraph_cycle_detection.feature`) and a Robot Framework
+  integration test (`robot/actor_compiler.robot`) to prevent regressions.
+
 ### Changed
 
 - **Diagnostics spec examples expanded to all 9 providers** (#5320): Updated the

features/actor_subgraph_cycle_detection.feature

@@ -0,0 +1,38 @@
+Feature: Cross-actor subgraph cycle detection reads actor_ref field
+  As a CleverAgents developer
+  I want the actor compiler to correctly detect cross-actor subgraph cycles
+  So that mutually-referencing actors raise SubgraphCycleError at compile time
+
+  Background:
+    Given the actor compiler is available
+
+  # ────────────────────────────────────────────────────────────
+  # Bug fix: actor_ref is a top-level NodeDefinition field
+  # ────────────────────────────────────────────────────────────
+
+  @tdd_issue @tdd_issue_1431
+  Scenario: Mutually-referencing actors raise SubgraphCycleError
+    Given actor "test/actor-a" has a subgraph node with actor_ref "test/actor-b"
+    And actor "test/actor-b" has a subgraph node with actor_ref "test/actor-a"
+    And a registry containing both actors
+    When I compile actor "test/actor-a" with the registry resolver
+    Then the compilation should raise SubgraphCycleError
+    And the cycle error message should mention "cycle"
+
+  @tdd_issue @tdd_issue_1431
+  Scenario: Non-cyclic subgraph reference compiles successfully
+    Given actor "test/actor-x" has a subgraph node with actor_ref "test/actor-y"
+    And actor "test/actor-y" has no subgraph nodes
+    And a registry containing both actors
+    When I compile actor "test/actor-x" with the registry resolver
+    Then the actor compilation should succeed
+    And the actor subgraph_refs should map "sub" to "test/actor-y"
+
+  @tdd_issue @tdd_issue_1431
+  Scenario: Subgraph node actor_ref is reflected in compiled metadata
+    Given actor "test/actor-p" has a subgraph node with actor_ref "test/actor-q"
+    And actor "test/actor-q" has no subgraph nodes
+    And a registry containing both actors
+    When I compile actor "test/actor-p" with the registry resolver
+    Then the actor compilation should succeed
+    And the compiled node "sub" should have subgraph set to "test/actor-q"

features/steps/actor_compiler_coverage_steps.py

@@ -135,7 +135,8 @@ def _subgraph_node(node_id: str, actor_ref: str = "") -> NodeDefinition:
         type=NodeType.SUBGRAPH,
         name=node_id.title(),
         description=f"Subgraph {node_id}",
-        config={"actor_ref": actor_ref},
+        config={},
+        actor_ref=actor_ref if actor_ref else None,
     )
 
 

features/steps/actor_compiler_steps.py

@@ -186,7 +186,8 @@ def step_given_subgraph_ref(context: Context, ref_name: str) -> None:
             type=NodeType.SUBGRAPH,
             name="Sub",
             description="Subgraph",
-            config={"actor_ref": ref_name},
+            config={},
+            actor_ref=ref_name,
         ),
     ]
     edges = [EdgeDefinition(from_node="main", to_node="sub")]
@@ -241,7 +242,8 @@ def step_given_outer_referencing_inner(
             type=NodeType.SUBGRAPH,
             name="Sub",
             description="Subgraph",
-            config={"actor_ref": inner_name},
+            config={},
+            actor_ref=inner_name,
         ),
     ]
     edges = [EdgeDefinition(from_node="main", to_node="sub")]
@@ -260,7 +262,8 @@ def step_given_resolver_cycle(context: Context, inner_name: str, back_ref: str)
             type=NodeType.SUBGRAPH,
             name="Child",
             description="Back-ref",
-            config={"actor_ref": back_ref},
+            config={},
+            actor_ref=back_ref,
         ),
     ]
     inner = _build_graph_config(inner_name, inner_nodes, [], "child", ["child"])

features/steps/actor_subgraph_cycle_detection_steps.py

@@ -0,0 +1,201 @@
+"""Step definitions for cross-actor subgraph cycle detection tests.
+
+Tests for features/actor_subgraph_cycle_detection.feature — validates that
+the actor compiler correctly reads actor_ref from the top-level
+NodeDefinition field (not from node.config) when detecting cross-actor
+subgraph cycles.
+
+This is the regression test for issue #1431: _detect_subgraph_cycles()
+was reading node.config.get("actor_ref", "") instead of node.actor_ref,
+causing cycle detection to always return an empty string and never detect
+cross-actor cycles.
+"""
+
+from __future__ import annotations
+
+from behave import given, then, when
+from behave.runner import Context
+
+from cleveragents.actor.compiler import (
+    SubgraphCycleError,
+    compile_actor,
+)
+from cleveragents.actor.schema import (
+    ActorConfigSchema,
+    ActorType,
+    EdgeDefinition,
+    NodeDefinition,
+    NodeType,
+    RouteDefinition,
+)
+
+
+# ────────────────────────────────────────────────────────────
+# Helpers
+# ────────────────────────────────────────────────────────────
+
+
+def _make_graph_actor(
+    name: str,
+    nodes: list[NodeDefinition],
+    edges: list[EdgeDefinition],
+    entry_node: str,
+    exit_nodes: list[str],
+) -> ActorConfigSchema:
+    """Build a minimal valid GRAPH actor for testing."""
+    route = RouteDefinition(
+        nodes=nodes,
+        edges=edges,
+        entry_node=entry_node,
+        exit_nodes=exit_nodes,
+    )
+    return ActorConfigSchema(
+        name=name,
+        type=ActorType.GRAPH,
+        description=f"Test actor {name}",
+        provider="openai",
+        model="gpt-4",
+        route=route,
+    )
+
+
+def _make_agent_node(node_id: str) -> NodeDefinition:
+    """Build a minimal AGENT node."""
+    return NodeDefinition(
+        id=node_id,
+        type=NodeType.AGENT,
+        name=node_id.title(),
+        description=f"Agent {node_id}",
+        config={"agent": "default"},
+    )
+
+
+def _make_subgraph_node(node_id: str, actor_ref: str) -> NodeDefinition:
+    """Build a SUBGRAPH node using the top-level actor_ref field.
+
+    The actor_ref is set as a first-class field on NodeDefinition, NOT
+    inside config.  This is the correct way to reference a subgraph actor.
+    """
+    return NodeDefinition(
+        id=node_id,
+        type=NodeType.SUBGRAPH,
+        name=node_id.title(),
+        description=f"Subgraph {node_id}",
+        config={},
+        actor_ref=actor_ref,
+    )
+
+
+# ────────────────────────────────────────────────────────────
+# Given steps
+# ────────────────────────────────────────────────────────────
+
+
+@given("the actor compiler is available")
+def step_compiler_available(context: Context) -> None:
+    """Ensure the actor compiler module is importable."""
+    context.actor_registry: dict[str, ActorConfigSchema] = {}
+
+
+@given('actor "{name}" has a subgraph node with actor_ref "{ref}"')
+def step_actor_has_subgraph_ref(context: Context, name: str, ref: str) -> None:
+    """Create a GRAPH actor with one agent node and one subgraph node."""
+    agent = _make_agent_node("start")
+    sub = _make_subgraph_node("sub", actor_ref=ref)
+    actor = _make_graph_actor(
+        name,
+        nodes=[agent, sub],
+        edges=[EdgeDefinition(from_node="start", to_node="sub")],
+        entry_node="start",
+        exit_nodes=["sub"],
+    )
+    context.actor_registry[name] = actor
+    context.actor_to_compile = name
+
+
+@given('actor "{name}" has no subgraph nodes')
+def step_actor_has_no_subgraph(context: Context, name: str) -> None:
+    """Create a GRAPH actor with only an agent node (no subgraph references)."""
+    agent = _make_agent_node("leaf")
+    actor = _make_graph_actor(
+        name,
+        nodes=[agent],
+        edges=[],
+        entry_node="leaf",
+        exit_nodes=["leaf"],
+    )
+    context.actor_registry[name] = actor
+
+
+@given("a registry containing both actors")
+def step_registry_contains_both(context: Context) -> None:
+    """Set up the resolver from the accumulated registry."""
+    registry = context.actor_registry
+
+    def resolver(actor_name: str) -> ActorConfigSchema | None:
+        return registry.get(actor_name)
+
+    context.resolver = resolver
+
+
+# ────────────────────────────────────────────────────────────
+# When steps
+# ────────────────────────────────────────────────────────────
+
+
+@when('I compile actor "{name}" with the registry resolver')
+def step_compile_actor(context: Context, name: str) -> None:
+    """Compile the named actor using the registry resolver."""
+    context.compile_error = None
+    context.compiled = None
+    actor = context.actor_registry[name]
+    try:
+        context.compiled = compile_actor(actor, actor_resolver=context.resolver)
+    except Exception as exc:
+        context.compile_error = exc
+
+
+# ────────────────────────────────────────────────────────────
+# Then steps
+# ────────────────────────────────────────────────────────────
+
+
+@then("the compilation should raise SubgraphCycleError")
+def step_raises_cycle_error(context: Context) -> None:
+    """Assert that compilation raised SubgraphCycleError."""
+    assert context.compile_error is not None, (
+        "Expected SubgraphCycleError but compilation succeeded"
+    )
+    assert isinstance(context.compile_error, SubgraphCycleError), (
+        f"Expected SubgraphCycleError, got {type(context.compile_error).__name__}: "
+        f"{context.compile_error}"
+    )
+
+
+@then("the actor compilation should succeed")
+def step_actor_compilation_succeeds(context: Context) -> None:
+    """Assert that compilation succeeded without errors."""
+    assert context.compile_error is None, (
+        f"Expected compilation to succeed but got: {context.compile_error}"
+    )
+    assert context.compiled is not None
+
+
+@then('the cycle error message should mention "{text}"')
+def step_cycle_error_mentions(context: Context, text: str) -> None:
+    """Assert that the cycle error message contains the given text."""
+    assert context.compile_error is not None
+    msg = str(context.compile_error)
+    assert text.lower() in msg.lower(), (
+        f"Expected '{text}' in error message, got: {msg}"
+    )
+
+
+@then('the actor subgraph_refs should map "{node}" to "{ref}"')
+def step_actor_subgraph_refs_map(context: Context, node: str, ref: str) -> None:
+    """Assert that the compiled metadata maps the node to the expected actor ref."""
+    assert context.compiled is not None
+    refs = context.compiled.metadata.subgraph_refs
+    assert refs.get(node) == ref, (
+        f"Expected subgraph_refs[{node!r}] == {ref!r}, got {refs}"
+    )

robot/actor_compiler.robot

@@ -42,3 +42,15 @@ Reject LLM Actor Compilation
     Should Be Equal As Integers    ${result.rc}    0
     Should Contain    ${result.stdout}    actor-compiler-expected-fail
     Should Contain    ${result.stdout}    GRAPH
+
+Detect Cross-Actor Subgraph Cycle Via actor_ref Field
+    [Documentation]    Verify that mutually-referencing actors raise SubgraphCycleError.
+    ...    This is the regression test for issue #1431: _detect_subgraph_cycles()
+    ...    was reading node.config.get("actor_ref") instead of node.actor_ref,
+    ...    causing cycle detection to silently fail.
+    [Tags]    slow
+    ${result}=    Run Process    ${PYTHON}    ${HELPER}    cycle-detect    dummy    cwd=${WORKSPACE}
+    Log    ${result.stdout}
+    Log    ${result.stderr}
+    Should Be Equal As Integers    ${result.rc}    0
+    Should Contain    ${result.stdout}    actor-compiler-cycle-detected

robot/helper_actor_compiler.py

@@ -66,6 +66,82 @@ def main() -> int:
             print(f"actor-compiler-fail: {exc}")
             return 1
 
+    if command == "cycle-detect":
+        # Test cross-actor cycle detection using actor_ref top-level field.
+        # Creates two mutually-referencing actors and verifies SubgraphCycleError
+        # is raised, confirming the fix for issue #1431.
+        from cleveragents.actor.compiler import SubgraphCycleError
+        from cleveragents.actor.schema import (
+            ActorType,
+            EdgeDefinition,
+            NodeDefinition,
+            NodeType,
+            RouteDefinition,
+        )
+
+        def _make_actor(
+            name: str, subgraph_ref: str | None = None
+        ) -> ActorConfigSchema:
+            if subgraph_ref is not None:
+                nodes = [
+                    NodeDefinition(
+                        id="start",
+                        type=NodeType.AGENT,
+                        name="Start",
+                        description="Start",
+                        config={"agent": "default"},
+                    ),
+                    NodeDefinition(
+                        id="sub",
+                        type=NodeType.SUBGRAPH,
+                        name="Sub",
+                        description="Subgraph",
+                        config={},
+                        actor_ref=subgraph_ref,
+                    ),
+                ]
+                edges = [EdgeDefinition(from_node="start", to_node="sub")]
+                entry, exits = "start", ["sub"]
+            else:
+                nodes = [
+                    NodeDefinition(
+                        id="leaf",
+                        type=NodeType.AGENT,
+                        name="Leaf",
+                        description="Leaf",
+                        config={"agent": "default"},
+                    )
+                ]
+                edges = []
+                entry, exits = "leaf", ["leaf"]
+            route = RouteDefinition(
+                nodes=nodes, edges=edges, entry_node=entry, exit_nodes=exits
+            )
+            return ActorConfigSchema(
+                name=name,
+                type=ActorType.GRAPH,
+                description=f"Test actor {name}",
+                model="gpt-4",
+                route=route,
+            )
+
+        actor_a = _make_actor("test/actor-a", subgraph_ref="test/actor-b")
+        actor_b = _make_actor("test/actor-b", subgraph_ref="test/actor-a")
+        registry = {"test/actor-a": actor_a, "test/actor-b": actor_b}
+
+        try:
+            compile_actor(actor_a, actor_resolver=registry.get)
+            print(
+                "actor-compiler-cycle-not-detected: FAIL — expected SubgraphCycleError"
+            )
+            return 1
+        except SubgraphCycleError as exc:
+            print(f"actor-compiler-cycle-detected: {exc}")
+            return 0
+        except Exception as exc:
+            print(f"actor-compiler-unexpected-error: {exc}")
+            return 1
+
     print(f"Unknown command: {command}")
     return 1
 

src/cleveragents/actor/compiler.py

@@ -137,7 +137,7 @@ def _map_node(node: NodeDefinition) -> lg_nodes.NodeConfig:
             config.get("function") if node.type == NodeType.CONDITIONAL else None
         ),
         tools=config.get("tools", []) if node.type == NodeType.TOOL else [],
-        subgraph=(config.get("actor_ref") if node.type == NodeType.SUBGRAPH else None),
+        subgraph=(node.actor_ref if node.type == NodeType.SUBGRAPH else None),
         metadata=dict(config),
     )
 
@@ -187,6 +187,11 @@ def _detect_subgraph_cycles(
     """Detect cycles in subgraph references across actors.
 
     Returns list of actor names forming a cycle, or empty list.
+
+    The actor reference is read from the top-level actor_ref field on
+    NodeDefinition, not from node.config.  Reading from config
+    would always return an empty string because actor_ref is stored as a
+    first-class field on the schema model.
     """
     if resolver is None:
         return []
@@ -194,7 +199,7 @@ def _detect_subgraph_cycles(
     for node in route_nodes:
         if node.type != NodeType.SUBGRAPH:
             continue
-        ref_name = node.config.get("actor_ref", "")
+        ref_name = node.actor_ref or ""
         if not ref_name:
             continue
         if ref_name in visited:
@@ -290,7 +295,7 @@ def compile_actor(
         all_lsp_bindings.extend(bindings)
 
         if node_def.type == NodeType.SUBGRAPH:
-            ref = node_def.config.get("actor_ref", "")
+            ref = node_def.actor_ref or ""
             if ref:
                 subgraph_refs[node_def.id] = ref