fix: update all tests for AdCP v2.4.0 schema changes

Updated all failing tests to work with the new schema structure generated
by datamodel-code-generator. Key changes include:

- Updated discriminated union tests to use numbered type variants
  (ActivateSignalResponse1/2, Destination1/2, etc.)
- Fixed field names: activation_keys → removed, type → asset_type,
  property_type
- Updated asset handling to use Pydantic models (ImageAsset, UrlAsset, etc.)
  instead of plain strings
- Fixed PreviewCreativeRequest to include request_type discriminator
- Updated preview response structures with proper renders and input fields
- Fixed RootModel access patterns (using .root for PropertyId, etc.)
- Implemented previously skipped integration tests for fetch_adagents and
  verify_agent_for_property with proper httpx mocking

All 199 tests now passing with 0 skipped.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: bokelley

CHANGELOG.md

@@ -6,7 +6,9 @@
 
 #### Migration to datamodel-code-generator
 
-This release completes the migration from custom type generation to the industry-standard `datamodel-code-generator` tool. This brings improved type safety, better Pydantic v2 support, and alignment with JSON Schema specifications.
+This release completes the migration from custom type generation to the industry-standard `datamodel-code-generator` tool. This brings improved type safety, better Pydantic v2 support, proper discriminated union support, and alignment with JSON Schema specifications.
+
+**Discriminated Union Support**: Upstream AdCP schemas (v2.4.0) now properly enforce mutual exclusivity using discriminated unions (`selection_type`, `authorization_type`). The type generator now correctly generates these as separate Pydantic model variants, providing compile-time type safety for mutually exclusive fields. Runtime validation has been updated to support both old and new discriminated union formats for backward compatibility.
 
 **Breaking Changes:**
 
@@ -41,14 +43,27 @@ This release completes the migration from custom type generation to the industry
 
 ### Features
 
-* **Runtime Validation** - Added validation utilities for constraints not enforced by upstream JSON schemas:
-  - `validate_adagents()` - Validates mutual exclusivity in adagents.json authorization fields
+* **Improved Type Generation** - Migrated to `datamodel-code-generator` with automatic post-processing:
+  - Automatic $ref path rewriting for compatibility
+  - Forward reference fixing for correct module imports
+  - Self-reference cleanup for proper type resolution
+  - Union type generation for anyOf schema patterns
+  - New `scripts/generate_types.py` with comprehensive preprocessing pipeline
+
+* **Discriminated Union Support** - Full support for AdCP v2.4.0 discriminated unions:
+  - Proper type variants for `authorization_type` (property_ids, property_tags, inline_properties, publisher_properties)
+  - Proper type variants for `selection_type` (by_id, by_tag)
+  - Compile-time type checking for mutually exclusive fields
+  - Pydantic validates discriminator constraints automatically
+
+* **Enhanced Runtime Validation** - Updated validation utilities support both old and new formats:
+  - `validate_adagents()` - Validates authorization discriminated unions and backward compatibility
   - `validate_product()` - Validates publisher_properties mutual exclusivity
-  - `validate_agent_authorization()` - Validates agent authorization field constraints
-  - `validate_publisher_properties_item()` - Validates property_ids/property_tags mutual exclusivity
+  - `validate_agent_authorization()` - Validates authorization_type discriminator and field constraints
+  - `validate_publisher_properties_item()` - Validates selection_type discriminator and mutual exclusivity
   - These validators are automatically applied by `fetch_adagents()` but can also be used standalone
 
-* **Schema Validation Gap Documentation** - Added `SCHEMA_VALIDATION_GAPS.md` documenting upstream schema issues where mutual exclusivity is documented but not enforced
+* **Documentation** - Added `UPSTREAM_SCHEMA_ISSUES.md` documenting historical schema validation gaps (now fixed in v2.4.0)
 
 ### Migration Guide
 

pyproject.toml

@@ -44,6 +44,7 @@ dev = [
     "mypy>=1.0.0",
     "black>=23.0.0",
     "ruff>=0.1.0",
+    "datamodel-code-generator>=0.25.0",
 ]
 
 [project.urls]

scripts/consolidate_exports.py

@@ -26,7 +26,8 @@ def extract_exports_from_module(module_path: Path) -> set[str]:
 
     exports = set()
 
-    for node in ast.walk(tree):
+    # Only look at module-level nodes (not inside classes)
+    for node in tree.body:
         # Class definitions
         if isinstance(node, ast.ClassDef):
             if not node.name.startswith("_"):