feat: add agent field to ToolContext

src/agents/run_internal/tool_execution.py

@@ -820,6 +820,7 @@ async def run_single_tool(func_tool: FunctionTool, tool_call: ResponseFunctionTo
                 context_wrapper,
                 tool_call.call_id,
                 tool_call=tool_call,
+                agent=agent,
             )
             agent_hooks = agent.hooks
             if config.trace_include_sensitive_data:

src/agents/tool_context.py

@@ -9,6 +9,7 @@
 from .usage import Usage
 
 if TYPE_CHECKING:
+    from .agent import Agent
     from .items import TResponseInputItem
     from .run_context import _ApprovalRecord
 
@@ -44,6 +45,9 @@ class ToolContext(RunContextWrapper[TContext]):
     tool_call: ResponseFunctionToolCall | None = None
     """The tool call object associated with this invocation."""
 
+    agent: Agent[Any] | None = None
+    """The agent that is calling this tool, if available."""
+
     def __init__(
         self,
         context: TContext,
@@ -53,6 +57,7 @@ def __init__(
         tool_arguments: str | object = _MISSING,
         tool_call: ResponseFunctionToolCall | None = None,
         *,
+        agent: Agent[Any] | None = None,
         turn_input: list[TResponseInputItem] | None = None,
         _approvals: dict[str, _ApprovalRecord] | None = None,
         tool_input: Any | None = None,
@@ -80,13 +85,15 @@ def __init__(
             else cast(str, tool_call_id)
         )
         self.tool_call = tool_call
+        self.agent = agent
 
     @classmethod
     def from_agent_context(
         cls,
         context: RunContextWrapper[TContext],
         tool_call_id: str,
         tool_call: ResponseFunctionToolCall | None = None,
+        agent: Agent[Any] | None = None,
     ) -> ToolContext:
         """
         Create a ToolContext from a RunContextWrapper.
@@ -105,6 +112,7 @@ def from_agent_context(
             tool_call_id=tool_call_id,
             tool_arguments=tool_args,
             tool_call=tool_call,
+            agent=agent,
             **base_values,
         )
         return tool_context

tests/test_tool_context.py

@@ -1,6 +1,7 @@
 import pytest
 from openai.types.responses import ResponseFunctionToolCall
 
+from agents import Agent
 from agents.run_context import RunContextWrapper
 from agents.tool_context import ToolContext
 from tests.utils.hitl import make_context_wrapper
@@ -36,3 +37,47 @@ def test_tool_context_from_agent_context_populates_fields() -> None:
     assert tool_ctx.tool_name == "test_tool"
     assert tool_ctx.tool_call_id == "call-123"
     assert tool_ctx.tool_arguments == '{"a": 1}'
+
+
+def test_tool_context_agent_none_by_default() -> None:
+    """Agent field defaults to None for backward compatibility."""
+    tool_call = ResponseFunctionToolCall(
+        type="function_call",
+        name="test_tool",
+        call_id="call-1",
+        arguments="{}",
+    )
+    ctx = make_context_wrapper()
+    tool_ctx = ToolContext.from_agent_context(ctx, tool_call_id="call-1", tool_call=tool_call)
+    assert tool_ctx.agent is None
+
+
+def test_tool_context_agent_from_agent_context() -> None:
+    """Agent is populated when passed to from_agent_context."""
+    agent = Agent(name="test-agent", instructions="do stuff")
+    tool_call = ResponseFunctionToolCall(
+        type="function_call",
+        name="test_tool",
+        call_id="call-2",
+        arguments="{}",
+    )
+    ctx = make_context_wrapper()
+    tool_ctx = ToolContext.from_agent_context(
+        ctx, tool_call_id="call-2", tool_call=tool_call, agent=agent
+    )
+    assert tool_ctx.agent is agent
+    assert tool_ctx.agent.name == "test-agent"
+
+
+def test_tool_context_agent_via_constructor() -> None:
+    """Agent is accessible when passed directly to the ToolContext constructor."""
+    agent = Agent(name="direct-agent", instructions="hi")
+    tool_ctx: ToolContext[dict[str, object]] = ToolContext(
+        context={},
+        tool_name="my_tool",
+        tool_call_id="call-3",
+        tool_arguments="{}",
+        agent=agent,
+    )
+    assert tool_ctx.agent is agent
+    assert tool_ctx.agent.name == "direct-agent"