Documentation Index
Fetch the complete documentation index at: https://docs.langsight.dev/llms.txt
Use this file to discover all available pages before exploring further.
Install
pip install langsight anthropic
from langsight.sdk import LangSightClient
from langsight.integrations.anthropic_sdk import langsight_anthropic_tool
client = LangSightClient(url="http://localhost:8000")
@langsight_anthropic_tool(client=client, server_name="my-tools")
async def get_weather(location: str) -> str:
"""Get current weather for a location."""
return f"72°F and sunny in {location}"
@langsight_anthropic_tool(client=client, server_name="my-tools")
async def search_docs(query: str) -> str:
"""Search the documentation."""
return await do_search(query)
tool_use, the execution is traced.
Pattern 2: Message response tracing
Trace all tool_use blocks from a message response:
from langsight.integrations.anthropic_sdk import AnthropicToolTracer
tracer = AnthropicToolTracer(
client=client,
agent_name="assistant",
session_id="sess-001",
)
# Your standard Anthropic SDK loop
response = await anthropic.messages.create(
model="claude-sonnet-4-6",
messages=[{"role": "user", "content": "What's the weather in NYC?"}],
tools=[weather_tool, search_tool],
)
# Record what tools the model requested
await tracer.trace_response(response)
# Execute tools and trace the execution
for block in response.content:
if block.type == "tool_use":
result = await tracer.execute_and_trace(
block.name, block.input, tool_handlers[block.name]
)
trace_response() captures the model’s decision. execute_and_trace() captures
the execution timing and result.
Pattern 3: Claude Agent SDK hooks
For the Claude Agent SDK’s higher-level agent runner:
from langsight.integrations.anthropic_sdk import LangSightClaudeAgentHooks
hooks = LangSightClaudeAgentHooks(
client=client,
agent_name="support-agent",
session_id="sess-001",
trace_id="trace-abc",
)
# Pass as lifecycle hooks
result = await runner.run(agent, hooks=hooks)
on_tool_start, on_tool_end, on_tool_error, and on_handoff.
What gets traced
| Field | Value |
|---|
tool_name | Tool function name or tool_use block name |
model_id | Model used (from response, e.g. claude-sonnet-4-6) |
input_tokens | Token usage from response |
output_tokens | Token usage from response |
input_args | Tool input parameters |
output_result | Tool return value (when using execute_and_trace) |
latency_ms | Auto-computed |
status | success, error, or timeout |
View traces
langsight sessions --id sess-001
