diff --git a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/CHANGELOG.md b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/CHANGELOG.md
index 95f69d6ded..4434fe558a 100644
--- a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/CHANGELOG.md
+++ b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/CHANGELOG.md
@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 - Document official package metadata and README for the OpenAI Agents instrumentation.
   ([#3859](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3859))
+- Populate instructions and tool definitions from Response obj.
+  ([#4196](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/4196))
 
 ## Version 0.1.0 (2025-10-15)
 
diff --git a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/src/opentelemetry/instrumentation/openai_agents/span_processor.py b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/src/opentelemetry/instrumentation/openai_agents/span_processor.py
index d1dce8ec5e..3a72ba5b07 100644
--- a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/src/opentelemetry/instrumentation/openai_agents/span_processor.py
+++ b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/src/opentelemetry/instrumentation/openai_agents/span_processor.py
@@ -1056,10 +1056,20 @@ def _build_content_payload(self, span: Span[Any]) -> ContentPayload:
 
         elif _is_instance_of(span_data, ResponseSpanData):
             span_input = getattr(span_data, "input", None)
+            response_obj = getattr(span_data, "response", None)
             if capture_messages and span_input:
                 payload.input_messages = (
                     self._normalize_messages_to_role_parts(span_input)
                 )
+
+            if (
+                capture_system
+                and response_obj
+                and hasattr(response_obj, "instructions")
+            ):
+                payload.system_instructions = self._normalize_to_text_parts(
+                    response_obj.instructions
+                )
             if capture_system and span_input:
                 sys_instr = self._collect_system_instructions(span_input)
                 if sys_instr:
@@ -2029,6 +2039,22 @@ def _get_attributes_from_response_span_data(
                 if output_tokens is not None:
                     yield GEN_AI_USAGE_OUTPUT_TOKENS, output_tokens
 
+            # Tool definitions from response
+            if self._capture_tool_definitions and hasattr(
+                span_data.response, "tools"
+            ):
+                yield (
+                    GEN_AI_TOOL_DEFINITIONS,
+                    safe_json_dumps(
+                        list(
+                            map(
+                                lambda tool: tool.to_dict(),
+                                span_data.response.tools,
+                            )
+                        )
+                    ),
+                )
+
         # Input/output messages
         if (
             self.include_sensitive_data
diff --git a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/tests/test_tracer.py b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/tests/test_tracer.py
index 1f21ab25c0..ed92b83d10 100644
--- a/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/tests/test_tracer.py
+++ b/instrumentation-genai/opentelemetry-instrumentation-openai-agents-v2/tests/test_tracer.py
@@ -25,6 +25,7 @@
     set_trace_processors,
     trace,
 )
+from openai.types.responses import FunctionTool  # noqa: E402
 
 from opentelemetry.instrumentation.openai_agents import (  # noqa: E402
     OpenAIAgentsInstrumentor,
@@ -62,6 +63,9 @@
 GEN_AI_OUTPUT_MESSAGES = getattr(
     GenAI, "GEN_AI_OUTPUT_MESSAGES", "gen_ai.output.messages"
 )
+GEN_AI_TOOL_DEFINITIONS = getattr(
+    GenAI, "GEN_AI_TOOL_DEFINITIONS", "gen_ai.tool.definitions"
+)
 
 
 def _instrument_with_provider(**instrument_kwargs):
@@ -487,8 +491,26 @@ def __init__(self, input_tokens: int, output_tokens: int) -> None:
     class _Response:
         def __init__(self) -> None:
             self.id = "resp-123"
+            self.instructions = "You are a helpful assistant."
             self.model = "gpt-4o-mini"
             self.usage = _Usage(42, 9)
+            self.tools = [
+                FunctionTool(
+                    name="get_current_weather",
+                    type="function",
+                    description="Get the current weather in a given location",
+                    parameters={
+                        "type": "object",
+                        "properties": {
+                            "location": {
+                                "title": "Location",
+                                "type": "string",
+                            },
+                        },
+                        "required": ["location"],
+                    },
+                )
+            ]
             self.output = [{"finish_reason": "stop"}]
 
     try:
@@ -516,6 +538,30 @@ def __init__(self) -> None:
         assert response.attributes[GenAI.GEN_AI_RESPONSE_FINISH_REASONS] == (
             "stop",
         )
+
+        system_instructions = json.loads(
+            response.attributes[GenAI.GEN_AI_SYSTEM_INSTRUCTIONS]
+        )
+        assert system_instructions == [
+            {"type": "text", "content": "You are a helpful assistant."}
+        ]
+        tool_definitions = json.loads(
+            response.attributes[GEN_AI_TOOL_DEFINITIONS]
+        )
+        assert tool_definitions == [
+            {
+                "type": "function",
+                "name": "get_current_weather",
+                "description": "Get the current weather in a given location",
+                "parameters": {
+                    "type": "object",
+                    "properties": {
+                        "location": {"title": "Location", "type": "string"},
+                    },
+                    "required": ["location"],
+                },
+            }
+        ]
     finally:
         instrumentor.uninstrument()
         exporter.clear()