• Improved Developer Experience: A more intuitive API means less code to write for tracing your application, simplifying the integration process.
• Unified Context Sharing: Seamlessly hook into the tracing context of the current span to update it or create child spans. This is particularly beneficial for integrating with other instrumented libraries.
• Broad Third-Party Integrations: Any library instrumented with OpenTelemetry will work out-of-the-box with the ABV SDK. Spans from these libraries are automatically captured and correctly nested within your ABV traces.

​

Quickstart

pip install abvdev

​

Using Observe Decorator

from abvdev import ABV, observe

abv = ABV(
    api_key="sk-abv-...", # your api key here
    host="https://app.abv.dev", # host="https://eu.app.abv.dev", for EU region
)
 
@observe
def my_function():
    return "Hello, world!" # Input/output and timings are automatically captured
 
my_function()
 
# Flush events in short-lived applications
abv.flush()

​

Using Context Managers

from abvdev import ABV

abv = ABV(
    api_key="sk-abv-...", # your api key here
    host="https://app.abv.dev", # host="https://eu.app.abv.dev", for EU region
)
 
# Create a span using a context manager
with abv.start_as_current_span(name="process-request") as span:
    # Your processing logic here
    span.update(output="Processing complete")
 
    # Create a nested generation for an LLM call
    with abv.start_as_current_observation(as_type='generation', name="llm-response", model="gpt-5-2025-08-07") as generation:
        # Your LLM call logic here
        generation.update(output="Generated response")
 
# All spans are automatically closed when exiting their context blocks
 
# Flush events in short-lived applications
abv.flush()

​

Using Manual Observations

from abvdev import ABV

abv = ABV(
    api_key="sk-abv-...", # your api key here
    host="https://app.abv.dev", # host="https://eu.app.abv.dev", for EU region
)
 
# Create a span without a context manager
span = abv.start_span(name="user-request")
 
# Your processing logic here
span.update(output="Request processed")
 
# Child spans must be created using the parent span object
nested_span = span.start_span(name="nested-span")
nested_span.update(output="Nested span output")
 
# Important: Manually end the span
nested_span.end()
 
# Important: Manually end the parent span
span.end()
 
# Flush events in short-lived applications
abv.flush()

​

Learn more

​

Key Features Supported

• Observability & Tracing: Comprehensive tracing of LLM applications
• Sessions: Group related traces by user journey
• User Tracking: Associate traces with specific users
• Metadata: Add structured context to traces
• Tags: Label and categorize traces
• Model Usage & Cost Tracking: Monitor tokens and costs
• Masking Sensitive Data: Redact PII and secrets
• Sampling: Control trace volume
• Prompt Management: Fetch and link prompts to traces
• Evaluations: Run evaluations and create datasets
• Guardrails: Implement LLM security guardrails

​

OTEL and ABV

• OTEL Trace: An OTEL-trace represents the entire lifecycle of a request or transaction as it moves through your application and its services. A trace is typically a sequence of operations, like an LLM generating a response followed by a parsing step. The root (first) span created in a sequence defines the OTEL-trace. OTEL-traces do not have a start and end time, they are defined by the root span.
• OTEL Span: A span represents a single unit of work or operation within a trace. Spans have a start and end time, a name, and can have attributes (key-value pairs of metadata). Spans can be nested to create a hierarchy, showing parent-child relationships between operations.
• ABV Trace: A ABV trace collects observations and holds trace attributes such as session_id, user_id as well as overall input and outputs. It shares the same ID as the OTEL trace and its attributes are set via specific OTEL span attributes that are automatically propagated to the ABV trace.
• ABV Observation: In ABV terminology, an “observation” is a ABV-specific representation of an OTEL span. It can be a generic span (ABV-span) or a specialized “generation” (ABV-generation) or a point in time event (ABV-event)
  • ABV Span: A ABV-span is a generic OTEL-span in ABV, designed for non-LLM operations.
  • ABV Generation: A ABV-generation is a specialized type of OTEL-span in ABV, designed specifically for Large Language Model (LLM) calls. It includes additional fields like model, model_parameters, usage_details (tokens), and cost_details.
  • ABV Event: A ABV-event tracks a point in time action.
• Context Propagation: OpenTelemetry automatically handles the propagation of the current trace and span context. This means when you call another function (whether it’s also traced by ABV, an OTEL-instrumented library, or a manually created span), the new span will automatically become a child of the currently active span, forming a correct trace hierarchy.