docs: Add weave by W&B as an observability option (#498)

* docs: Add weave by W&B as an observability option

* Updated menu item name and Added screenshots

---------

Co-authored-by: Lavi Nigam <[email protected]>

Author: xprilion

docs/observability/weave.md

@@ -0,0 +1,127 @@
+# Agent Observability with Weave by WandB
+
+[Weave by Weights & Biases (WandB)](https://weave-docs.wandb.ai/) provides a powerful platform for logging and visualizing model calls. By integrating Google ADK with Weave, you can track and analyze your agent's performance and behavior using OpenTelemetry (OTEL) traces.
+
+## Prerequisites
+
+1. Sign up for an account at [WandB](https://wandb.ai).
+
+2. Obtain your API key from [WandB Authorize](https://wandb.ai/authorize).
+
+3. Configure your environment with the required API keys:
+
+   ```bash
+   export WANDB_API_KEY=<your-wandb-api-key>
+   export GOOGLE_API_KEY=<your-google-api-key>
+   ```
+
+## Install Dependencies
+
+Ensure you have the necessary packages installed:
+
+```bash
+pip install google-adk opentelemetry-sdk opentelemetry-exporter-otlp-proto-http
+```
+
+## Sending Traces to Weave
+
+This example demonstrates how to configure OpenTelemetry to send Google ADK traces to Weave.
+
+```python
+# math_agent/agent.py
+
+import base64
+import os
+from opentelemetry.exporter.otlp.proto.http.trace_exporter import OTLPSpanExporter
+from opentelemetry.sdk import trace as trace_sdk
+from opentelemetry.sdk.trace.export import SimpleSpanProcessor
+from opentelemetry import trace
+
+from google.adk.agents import LlmAgent
+from google.adk.tools import FunctionTool
+
+from dotenv import load_dotenv
+
+load_dotenv()
+
+# Configure Weave endpoint and authentication
+WANDB_BASE_URL = "https://trace.wandb.ai"
+PROJECT_ID = "your-entity/your-project"  # e.g., "teamid/projectid"
+OTEL_EXPORTER_OTLP_ENDPOINT = f"{WANDB_BASE_URL}/otel/v1/traces"
+
+# Set up authentication
+WANDB_API_KEY = os.getenv("WANDB_API_KEY")
+AUTH = base64.b64encode(f"api:{WANDB_API_KEY}".encode()).decode()
+
+OTEL_EXPORTER_OTLP_HEADERS = {
+    "Authorization": f"Basic {AUTH}",
+    "project_id": PROJECT_ID,
+}
+
+# Create the OTLP span exporter with endpoint and headers
+exporter = OTLPSpanExporter(
+    endpoint=OTEL_EXPORTER_OTLP_ENDPOINT,
+    headers=OTEL_EXPORTER_OTLP_HEADERS,
+)
+
+# Create a tracer provider and add the exporter
+tracer_provider = trace_sdk.TracerProvider()
+tracer_provider.add_span_processor(SimpleSpanProcessor(exporter))
+
+# Set the global tracer provider BEFORE importing/using ADK
+trace.set_tracer_provider(tracer_provider)
+
+# Define a simple tool for demonstration
+def calculator(a: float, b: float) -> str:
+    """Add two numbers and return the result.
+
+    Args:
+        a: First number
+        b: Second number
+
+    Returns:
+        The sum of a and b
+    """
+    return str(a + b)
+
+calculator_tool = FunctionTool(func=calculator)
+
+# Create an LLM agent
+root_agent = LlmAgent(
+    name="MathAgent",
+    model="gemini-2.0-flash-exp",
+    instruction=(
+        "You are a helpful assistant that can do math. "
+        "When asked a math problem, use the calculator tool to solve it."
+    ),
+    tools=[calculator_tool],
+)
+```
+
+## View Traces in Weave dashboard
+
+Once the agent runs, all its traces are logged to the corresponding project on [the Weave dashboard](https://wandb.ai/home).
+
+![Traces in Weave](https://wandb.github.io/weave-public-assets/google-adk/traces-overview.png)
+
+You can view a timeline of calls that your ADK agent made during execution -
+
+![Timeline view](https://wandb.github.io/weave-public-assets/google-adk/adk-weave-timeline.gif)
+
+
+## Notes
+
+- **Environment Variables**: Ensure your environment variables are correctly set for both WandB and Google API keys.
+- **Project Configuration**: Replace `<your-entity>/<your-project>` with your actual WandB entity and project name.
+- **Entity Name**: You can find your entity name by visiting your [WandB dashboard](https://wandb.ai/home) and checking the **Teams** field in the left sidebar.
+- **Tracer Provider**: It's critical to set the global tracer provider before using any ADK components to ensure proper tracing.
+
+By following these steps, you can effectively integrate Google ADK with Weave, enabling comprehensive logging and visualization of your AI agents' model calls, tool invocations, and reasoning processes.
+
+## Resources
+
+- **[Send OpenTelemetry Traces to Weave](https://weave-docs.wandb.ai/guides/tracking/otel)** - Comprehensive guide on configuring OTEL with Weave, including authentication and advanced configuration options.
+
+- **[Navigate the Trace View](https://weave-docs.wandb.ai/guides/tracking/trace-tree)** - Learn how to effectively analyze and debug your traces in the Weave UI, including understanding trace hierarchies and span details.
+
+- **[Weave Integrations](https://weave-docs.wandb.ai/guides/integrations/)** - Explore other framework integrations and see how Weave can work with your entire AI stack.

mkdocs.yml

@@ -166,6 +166,7 @@ nav:
     - AgentOps: observability/agentops.md
     - Arize AX: observability/arize-ax.md
     - Phoenix: observability/phoenix.md
+    - W&B Weave: observability/weave.md
     - Logging: observability/logging.md
   - Evaluate:
     - evaluate/index.md