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Phoenix

4.1
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Phoenix is an open-source tool for AI developers to trace, evaluate, and optimize their Large Language Models (LLMs). It provides tools to understand how your AI makes decisions, experiment with prompts, and identify problems like incorrect outputs, helping you build more reliable and effective AI applications faster.

Free Option

About Phoenix

Who It's For

Phoenix is for AI developers and engineers building with Large Language Models (LLMs). It helps you understand, test, and improve your AI applications. This open-source tool offers full control to debug and optimize your AI performance.

What You Get

You get clear tracing of your AI's decisions and an interactive prompt playground to test ideas. Phoenix also provides tools to evaluate AI responses and incorporate human feedback. It helps you group data to spot performance issues easily.

How It Works

Phoenix sets up easily using OpenTelemetry, collecting data from your AI applications. It lets you trace AI decisions, experiment with prompts, and evaluate responses. This helps you quickly find and fix problems, such as when your AI gives incorrect or misleading information.

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Features & Capabilities

๐Ÿ“Š LLM Observability & Debugging

Application Tracing

Provides total visibility into LLM application data with automatic or manual instrumentation.

Dataset Clustering & Visualization

Uncovers semantically similar questions, document chunks, and responses using embeddings to isolate poor performance.

Real-time LLM Evaluation

Enables evaluation, experimentation, and optimization of AI products in real time.

Model Interpretability

Visualizes complex LLM decision-making and flags when and where models fail or produce poor responses.

๐Ÿงช Prompt Engineering & Evaluation

Interactive Prompt Playground

Offers a fast, flexible sandbox for prompt and model iteration, output visualization, and debugging.

Streamlined Evaluations

Leverages a high-speed evaluation library with pre-built, customizable templates for any task.

Human Feedback Integration

Incorporates human feedback into the evaluation process to enhance model assessment.

โš™๏ธ Platform Architecture & Integration

OpenTelemetry-based Foundation

Uses OpenTelemetry for seamless setup, full transparency, and freedom from vendor lock-in.

Open Source & Self-Hostable

Provided as a fully open-source solution, allowing for self-hosting without feature restrictions.

Broad LLM Tool Compatibility

Works with all major LLM tools and frameworks, supporting easy integration into existing workflows.

Use Cases

Accelerating LLM Application Debugging and Iteration

AI engineers face challenges in quickly identifying root causes of poor LLM performance, such as hallucinations or irrelevant responses, during development. Phoenix provides interactive tracing for total visibility, an interactive prompt playground for rapid experimentation, and visual dataset clustering to efficiently debug and iterate on prompts and models, significantly improving application quality and development speed.

AI/ML DevelopmentFor: AI Engineers

Ensuring Production LLM Performance and Observability

For LLM applications in production, it's crucial to continuously monitor performance, detect regressions, and ensure ongoing reliability. Phoenix enables streamlined evaluations with customizable templates, incorporates human feedback, and provides extensive observability utilities to proactively track model behavior, identify performance degradation, and manage the entire LLM lifecycle effectively.

MLOpsFor: MLOps Engineers

Deep Root Cause Analysis for Complex LLM Behaviors

When LLM applications generate unexpected or problematic outputs like hallucinations or problematic responses, data scientists need deep visibility to diagnose the issue. Phoenix offers application tracing to visualize complex LLM decision-making workflows and dataset clustering to uncover semantically similar inputs or outputs, enabling precise identification and resolution of failure points related to retrieval and tool execution.

Data ScienceFor: Data Scientists

Frequently asked questions

Tags

Specifications

Deployment
Browser
API
Self-hosted
Cloud
Target Audience
Individual
Startup
Business
Complexity
Expert

Pricing

Phoenix

Per one-time

Free
  • Users Unlimited
  • Trace spans User managed
  • Ingestion volume User managed
  • Projects User managed
  • Retention User managed
  • Dedicated support (add-on)

AX Free

Per monthly

Free
  • Users: 1 user
  • Trace spans: 25k spans per month
  • Ingestion volume: 1 GB per month
  • Projects: N/A
  • Retention: 7 days
  • Online evals
  • Product observability (monitors & custom metrics)
  • Community support

AX Pro

Per monthly

$50
  • Includes all features from the AX Free plan
  • Users: Up to 3 users
  • Trace spans: 100k spans per month
  • Additional traces: $10 per Million
  • Ingestion volume: 50 GB per month
  • Additional ingestion: $3 per GB
  • Retention: 15 days
  • Alyx Co-pilot
  • Email support

AX Enterprise

Per monthly

Free
  • Includes all features from the AX Pro plan
  • Users: Unlimited
  • Trace spans: Billions+
  • Ingestion volume: 5 TB+
  • Projects: Custom
  • Retention: Configurable
  • Dedicated support
  • Uptime SLA
  • Custom data limits
  • SOC2 reports and HIPAA
  • Training sessions
  • DataFabric Connect
  • Data Residency (Self-Hosting add-on)
  • Multi-region deployments (Self-Hosting add-on)

โœ“ Free plan โ€ข โœ“ Plans from $50 / monthly โ€ข โœ“ Enterprise options

Integrations

GitHub
Slack
LlamaIndex
Langchain
OpenAI
Mistral

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