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Galtea’s tracing feature captures every operation your agent performs—tool calls, retrieval operations, LLM invocations—with minimal code changes. This tutorial shows you how to instrument your agent and collect traces.
For detailed information about trace properties, node types, and hierarchy, see the Trace concept page.

1. The @trace Decorator

Add the @trace decorator to any function you want to track. It automatically captures: name, inputs, outputs, timing, errors, and parent-child relationships.
@trace(name="db_call", type=TraceType.TOOL)
def my_function(query: str) -> str:
    result = db.query(query)
    return result

2. The start_trace Context Manager

For fine-grained control over specific code blocks, use start_trace.
def get_user(user_id: str) -> str:
    with start_trace(
        "database_query", type=TraceType.TOOL, input={"user_id": user_id}
    ) as span:
        query = f"SELECT * FROM users WHERE id = {user_id}"
        result = db.query(query)
        span.update(output=result, metadata={"query": query})
    return result
The span.update() method lets you add output, metadata, or change the type after execution.
Both @trace and start_trace automatically capture parent-child relationships between operations when they are nested inside each other, giving you a full hierarchical view of your agent’s behavior.

3. Collect and Send Traces to Galtea

Traces are built locally. To send them to Galtea, you need to associate them with an inference_result_id. There are two approaches:

Automatic Collection

Use inference_results.generate() or simulator.simulate() for hands-free trace management. These methods automatically:
  1. Set the trace context with the correct IDs
  2. Execute your agent
  3. Flush all collected traces to Galtea
  4. Clean up the context

Single-Turn with generate()

Requires implementing the Agent abstract class:
class MyAgent(Agent):
    @trace(type=TraceType.RETRIEVER)
    def search(self, query: str) -> list[dict]:
        return [{"id": "doc_1", "content": "..."}]

    @trace(type=TraceType.GENERATION)
    def generate(self, context: list, query: str) -> str:
        return "Based on the context..."

    @trace(type=TraceType.AGENT)
    def call(self, input: AgentInput) -> AgentResponse:
        query = input.last_user_message_str()
        docs = self.search(query)
        response = self.generate(docs, query)
        return AgentResponse(content=response, retrieval_context=str(docs))


# Setup
session = galtea.sessions.create(version_id=version.id, is_production=True)
agent = MyAgent()

# Everything is handled automatically
inference_result = galtea.inference_results.generate(
    agent=agent, session=session, user_input="What's the price?"
)
# Traces are collected, associated with inference_result.id, and flushed automatically

Multi-Turn with simulate()

When using the Conversation Simulator, tracing works out-of-the-box. Decorate your agent methods with @trace and run:
    result = galtea.simulator.simulate(
        session_id=simulation_session.id, agent=agent, max_turns=5
    )
    # Traces are saved automatically for each turn

Manual Collection

For full control, use set_context() and clear_context() to manually manage the trace lifecycle:
# Define traced functions
@trace(type=TraceType.RETRIEVER)
def search(query: str) -> list[dict]:
    return [{"id": "doc_1", "content": "..."}]


@trace(type=TraceType.GENERATION)
def generate(context: list, query: str) -> str:
    return "Based on the context..."


@trace(type=TraceType.AGENT)
def run_agent(query: str) -> str:
    docs = search(query)
    return generate(docs, query)


# Setup
manual_session = galtea.sessions.create(version_id=version.id, is_production=True)
user_input = "What's the price?"

# 1. Create inference result first (to get the ID)
manual_inference_result = galtea.inference_results.create(
    session_id=manual_session.id,
    input=user_input,
    output=None,  # Will update later
)

# 2. Set trace context with the inference result ID
token = set_context(inference_result_id=manual_inference_result.id)

try:
    # 3. Run your logic - all @trace calls will be associated with this inference result
    response = run_agent(user_input)

    # 4. Update inference result with the output
    galtea.inference_results.update(
        inference_result_id=manual_inference_result.id, output=response
    )
finally:
    # 5. Clear context and flush traces to Galtea
    clear_context(token)  # flush=True by default
clear_context(token, flush=True) automatically flushes all pending traces for the inference result before clearing. Set flush=False if you want to discard traces without sending them.

Summary

MethodControlBest For
Automatic (generate())SimplifiedProduction single-turn inference
Automatic (simulate())Built-inMulti-turn conversation testing
Manual (set_context/clear_context)FullCustom workflows, debugging, testing

Next Steps