The LLMOps Stack: OpenTelemetry, Self-Host and Pricing-Model Comparison 2026

A structured comparison of 19 production LLM-operations tools across four stack layers (gateway/routing, observability/tracing, evaluation/testing, guardrails/safety) on five interoperability and cost dimensions: OpenTelemetry-native support, self-host availability, open-source licensing, pricing model, and whether evaluation and guardrails are built in. Compiled vendor-neutral with conflict disclosure; each cell read from the tool's own documentation, repository, or pricing page. Methodology and full sourcing at https://nesyona.com/research/llmops-stack-comparison-2026/ . License CC-BY 4.0.