chore: allow custom tracer provider to Agent

Author: poshinchen

src/strands/agent/agent.py

@@ -20,6 +20,7 @@
 from uuid import uuid4
 
 from opentelemetry import trace
+from opentelemetry.sdk.trace import TracerProvider
 
 from ..event_loop.event_loop import event_loop_cycle
 from ..handlers.callback_handler import CompositeCallbackHandler, PrintingCallbackHandler, null_callback_handler
@@ -216,6 +217,7 @@ def __init__(
         record_direct_tool_call: bool = True,
         load_tools_from_directory: bool = True,
         trace_attributes: Optional[Mapping[str, AttributeValue]] = None,
+        tracer_provider: Optional[TracerProvider] = None,
     ):
         """Initialize the Agent with the specified configuration.
 
@@ -248,6 +250,7 @@ def __init__(
             load_tools_from_directory: Whether to load and automatically reload tools in the `./tools/` directory.
                 Defaults to True.
             trace_attributes: Custom trace attributes to apply to the agent's trace span.
+            tracer_provider: Custom trace provider to apply to the agents' tracer.
 
         Raises:
             ValueError: If max_parallel_tools is less than 1.
@@ -306,7 +309,7 @@ def __init__(
         self.event_loop_metrics = EventLoopMetrics()
 
         # Initialize tracer instance (no-op if not configured)
-        self.tracer = get_tracer()
+        self.tracer = get_tracer(tracer_provider=tracer_provider)
         self.trace_span: Optional[trace.Span] = None
 
         self.tool_caller = Agent.ToolCaller(self)

src/strands/agent/conversation_manager/sliding_window_conversation_manager.py

@@ -140,7 +140,7 @@ def reduce_context(self, agent: "Agent", e: Optional[Exception] = None) -> None:
             if results_truncated:
                 logger.debug("message_index=<%s> | tool results truncated", last_message_idx_with_tool_results)
                 return
-        
+
         # Try to trim index id when tool result cannot be truncated anymore
         # If the number of messages is less than the window_size, then we default to 2, otherwise, trim to window size
         trim_index = 2 if len(messages) <= self.window_size else len(messages) - self.window_size

src/strands/telemetry/tracer.py

@@ -11,12 +11,15 @@
 from importlib.metadata import version
 from typing import Any, Dict, Mapping, Optional
 
-from opentelemetry import trace
+from opentelemetry import propagate, trace
+from opentelemetry.baggage.propagation import W3CBaggagePropagator
 from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
+from opentelemetry.propagators.composite import CompositePropagator
 from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.trace import TracerProvider
 from opentelemetry.sdk.trace.export import BatchSpanProcessor, ConsoleSpanExporter, SimpleSpanProcessor
 from opentelemetry.trace import StatusCode
+from opentelemetry.trace.propagation.tracecontext import TraceContextTextMapPropagator
 
 from ..agent.agent_result import AgentResult
 from ..types.content import Message, Messages
@@ -94,6 +97,7 @@ def __init__(
         otlp_endpoint: Optional[str] = None,
         otlp_headers: Optional[Dict[str, str]] = None,
         enable_console_export: Optional[bool] = None,
+        tracer_provider: Optional[TracerProvider] = None,
     ):
         """Initialize the tracer.
 
@@ -102,6 +106,7 @@ def __init__(
             otlp_endpoint: OTLP endpoint URL for sending traces.
             otlp_headers: Headers to include with OTLP requests.
             enable_console_export: Whether to also export traces to console.
+            tracer_provider: Optional existing TracerProvider to use instead of creating a new one.
         """
         # Check environment variables first
         env_endpoint = os.environ.get("OTEL_EXPORTER_OTLP_ENDPOINT")
@@ -133,10 +138,22 @@ def __init__(
 
         self.service_name = service_name
         self.otlp_headers = otlp_headers or {}
-        self.tracer_provider: Optional[TracerProvider] = None
+        self.tracer_provider = tracer_provider
         self.tracer: Optional[trace.Tracer] = None
 
-        if self.otlp_endpoint or self.enable_console_export:
+        propagate.set_global_textmap(
+            CompositePropagator(
+                [
+                    W3CBaggagePropagator(),
+                    TraceContextTextMapPropagator(),
+                ]
+            )
+        )
+        if self.tracer_provider:
+            # Use the provided tracer provider directly
+            self.tracer = self.tracer_provider.get_tracer(self.service_name)
+        elif self.otlp_endpoint or self.enable_console_export:
+            # Create our own tracer provider
             self._initialize_tracer()
 
     def _initialize_tracer(self) -> None:
@@ -549,6 +566,7 @@ def get_tracer(
     otlp_endpoint: Optional[str] = None,
     otlp_headers: Optional[Dict[str, str]] = None,
     enable_console_export: Optional[bool] = None,
+    tracer_provider: Optional[TracerProvider] = None,
 ) -> Tracer:
     """Get or create the global tracer.
 
@@ -557,18 +575,22 @@ def get_tracer(
         otlp_endpoint: OTLP endpoint URL for sending traces.
         otlp_headers: Headers to include with OTLP requests.
         enable_console_export: Whether to also export traces to console.
+        tracer_provider: Optional existing TracerProvider to use instead of creating a new one.
 
     Returns:
         The global tracer instance.
     """
     global _tracer_instance
 
-    if _tracer_instance is None or (otlp_endpoint and _tracer_instance.otlp_endpoint != otlp_endpoint):  # type: ignore[unreachable]
+    if (
+        _tracer_instance is None or (otlp_endpoint and _tracer_instance.otlp_endpoint != otlp_endpoint)  # type: ignore[unreachable]
+    ):
         _tracer_instance = Tracer(
             service_name=service_name,
             otlp_endpoint=otlp_endpoint,
             otlp_headers=otlp_headers,
             enable_console_export=enable_console_export,
+            tracer_provider=tracer_provider,
         )
 
     return _tracer_instance

tests/strands/telemetry/test_tracer.py

@@ -4,7 +4,10 @@
 from unittest import mock
 
 import pytest
-from opentelemetry.trace import StatusCode  # type: ignore
+from opentelemetry.trace import (
+    NoOpTracerProvider,
+    StatusCode,  # type: ignore
+)
 
 from strands.telemetry.tracer import JSONEncoder, Tracer, get_tracer, serialize
 from strands.types.streaming import Usage
@@ -104,6 +107,12 @@ def env_with_both():
         yield
 
 
+@pytest.fixture
+def mock_initialize():
+    with mock.patch("strands.telemetry.tracer.Tracer._initialize_tracer") as mock_initialize:
+        yield mock_initialize
+
+
 def test_init_default():
     """Test initializing the Tracer with default parameters."""
     tracer = Tracer()
@@ -486,6 +495,22 @@ def test_initialize_tracer_with_invalid_otlp_endpoint(
     mock_set_tracer_provider.assert_called_once_with(mock_tracer_provider.return_value)
 
 
+def test_initialize_tracer_with_custom_tracer_provider(mock_initialize):
+    """Test initializing the tracer with NoOpTracerProvider."""
+    noop_provider = NoOpTracerProvider()
+
+    tracer = Tracer(tracer_provider=noop_provider)
+
+    # Verify the NoOp provider is used
+    assert tracer.tracer_provider == noop_provider
+
+    # Verify tracer is set (will be a NoOp tracer)
+    assert tracer.tracer is not None
+
+    # Verify _initialize_tracer was NOT called
+    mock_initialize.assert_not_called()
+
+
 def test_end_span_with_exception_handling(mock_span):
     """Test ending a span with exception handling."""
     tracer = Tracer()