Enable non-strict output types

Author: rm-openai

src/agents/agent.py

@@ -144,6 +144,14 @@ class Agent(Generic[TContext]):
     output_type: type[Any] | None = None
     """The type of the output object. If not provided, the output will be `str`."""
 
+    output_schema_strict: bool = True
+    """Whether the output JSON schema passed to the LLM should be strict.
+
+    We **strongly** recommend setting this to True, as it increases the likelihood of correct JSON
+    being produced. However, for output types that cannot be converted to strict JSON, you can
+    set this to False.
+    """
+
     hooks: AgentHooks[TContext] | None = None
     """A class that receives callbacks on various lifecycle events for this agent.
     """

src/agents/agent_output.py

@@ -71,7 +71,14 @@ def __init__(self, output_type: type[Any], strict_json_schema: bool = True):
             self._output_schema = self._type_adapter.json_schema()
 
         if self.strict_json_schema:
-            self._output_schema = ensure_strict_json_schema(self._output_schema)
+            try:
+                self._output_schema = ensure_strict_json_schema(self._output_schema)
+            except UserError as e:
+                raise UserError(
+                    "Strict JSON schema is enabled, but the output type is not valid. "
+                    "Either make the output type strict, or pass output_schema_strict=False to "
+                    "your Agent()"
+                ) from e
 
     def is_plain_text(self) -> bool:
         """Whether the output type is plain text (versus a JSON object)."""

src/agents/run.py

@@ -934,7 +934,7 @@ def _get_output_schema(cls, agent: Agent[Any]) -> AgentOutputSchema | None:
         if agent.output_type is None or agent.output_type is str:
             return None
 
-        return AgentOutputSchema(agent.output_type)
+        return AgentOutputSchema(agent.output_type, strict_json_schema=agent.output_schema_strict)
 
     @classmethod
     def _get_handoffs(cls, agent: Agent[Any]) -> list[Handoff]: