Fiddler AI vs Pulsar

Fiddler AI provides observability and security for AI agents and predictive applications. It evaluates agents and models during development, then monitors them in production, with diagnostics spanning more than 100 built-in and custom metrics such as hallucination, toxicity, PII/PHI, drift, performance, and business KPIs. Real-time guardrails can detect risks and pause, reroute, or escalate agent actions. The platform records decisions, actions, evaluations, and policy outcomes to support audit evidence for requirements including GDPR, HIPAA, NAIC, and SR 11-7. It names LangGraph, Amazon Bedrock, and AWS Strands Agents as native framework support, and is built on OpenTelemetry standards. Deployment options include cloud SaaS, VPC, on-premises, and air-gapped environments. Fiddler says it is SOC 2 Type II certified, complies with HIPAA, and encrypts data in transit and at rest. Plans include Free at free, Developer at a price agreed with the maker billed per trace, and Enterprise with no listed price. The company was founded in 2018 and is headquartered in Palo Alto, California.

Pulsar is a free, open-source, self-hosted system for monitoring machine learning models in production. It tracks model drift, concept drift, and performance by comparing incoming behavior with training data used as a baseline. An SDK and containerised ingestion service collect model inputs and outputs into a time series database, supporting historical and real-time data. The current database integration is InfluxDB, and the project is designed for large ingestion volumes without degraded performance. A scheduler checks drift and can trigger standard or customised alerts when metrics reach thresholds. Grafana displays drift measures across selected time ranges and user-defined features. Available drift tests include Kullback-Leibler divergence, Kolmogorov-Smirnov, Levene, and Wasserstein; performance measures include accuracy, recall, F1 score, Brier score, mean squared error, and R2. Deployment logos cover Flask, FastAPI, TensorFlow Extended, Seldon, AWS, Azure, Google Cloud, and Grafana.