@@ -0,0 +123,4 @@
+
+
+# ------------------------------------------------------------------
+# Decision dict inputs / validators

@@ -0,0 +163,4 @@
+    """Validate a plan tree output (list of root node dicts)."""
+    if not isinstance(data, list):
+        return OutputValidationResult(
+            valid=False, message="Plan tree root must be a list",

@@ -0,0 +282,4 @@
+            errors.append(f"{key}: invalid format")
+
+    dtype = data.get("type")
+    if not isinstance(dtype, str) or not dtype:

@@ -50,1 +37,3 @@
-        And it should report errors including "duplicate sequence"
+  Scenario: Plan tree root is not a list fails
+    When I validate a string "not a list" as plan tree
+    Then the validation result is invalid

@@ -0,0 +9,4 @@
+    "Output validation is flexible - checks structural components,
+     not exact character matching."
+    (docs/specification.md Testing Strategy)
+

@@ -0,0 +217,4 @@
+    if not type_missing and dtype is not None and dtype not in _VALID_DECISION_TYPES:
+        errors.append(f"{prefix}.type: unexpected {dtype!r}")
+    seq = node.get("sequence")
+    if not ("sequence" in set(node.keys()) or seq is None) and not _is_valid_sequence(seq):

@@ -0,0 +294,4 @@
+    for key, check in [("question", str), ("chosen", str)]:
+        val = data.get(key)
+        if not isinstance(val, (str, type(None))) and val is not None:
+            errors.append(f"{key}: expected string or null")

@@ -0,0 +330,4 @@
+    """Validate a structured session output envelope."""
+    if not isinstance(data, dict):
+        return OutputValidationResult(valid=False, message="Structured output must be a dict", errors=[f"Expected dict, got {type(data).__name__}"], schema_name="structured_output_root")
+

@@ -0,0 +220,4 @@
+    if (
+        not ("sequence" in set(node.keys()) or seq is None)
+    ) and not _is_valid_sequence(seq):
+        pass  # Missing already reported above

@@ -0,0 +306,4 @@
+    if not _is_valid_sequence(seq):
+        errors.append("sequence: expected non-negative int")
+
+    _STR = str

@@ -50,1 +37,3 @@
-        And it should report errors including "duplicate sequence"
+  Scenario: Plan tree root is not a list fails
+    When I validate a string "not a list" as plan tree
+    Then the validation result is invalid

@@ -0,0 +9,4 @@
+    "Output validation is flexible - checks structural components,
+     not exact character matching."
+    (docs/specification.md Testing Strategy)
+

@@ -0,0 +217,4 @@
+    if not type_missing and dtype is not None and dtype not in _VALID_DECISION_TYPES:
+        errors.append(f"{prefix}.type: unexpected {dtype!r}")
+    seq = node.get("sequence")
+    if not ("sequence" in set(node.keys()) or seq is None) and not _is_valid_sequence(seq):

@@ -0,0 +294,4 @@
+    for key, check in [("question", str), ("chosen", str)]:
+        val = data.get(key)
+        if not isinstance(val, (str, type(None))) and val is not None:
+            errors.append(f"{key}: expected string or null")

@@ -0,0 +330,4 @@
+    """Validate a structured session output envelope."""
+    if not isinstance(data, dict):
+        return OutputValidationResult(valid=False, message="Structured output must be a dict", errors=[f"Expected dict, got {type(data).__name__}"], schema_name="structured_output_root")
+