Alternatives to Langfuse

Fiddler AI is an AI observability and guardrails vendor. Its published material describes guardrails that enforce policy inline on an agent's request and response path in under 80ms, stopping violations before data leaves the customer network rather than flagging them afterwards, and states that every enforcement decision is recorded with who triggered it and what happened. It is sold on three plans, with the Developer plan usage-based at $0.002 per trace, and is deployable as SaaS, VPC or on-premises, including AWS GovCloud. The vendor states its users include Fortune 100 organizations in regulated sectors such as financial services, healthcare, insurance and government, and lists inclusion in four Forrester, Gartner and IDC analyst reports. No compliance certificate, auditor or report date is published on the source page, and no insurance cover, customer indemnity, coverage limit, outcome-linked payment or settlement mechanism is published. All statements above are drawn from the vendor's own homepage, which is a primary source for what the vendor claims about itself.

Keywords AI supplies an AI observability platform, which the page checked refers to as Respan. Per the vendor's own homepage, every LLM call, tool run, retrieval and agent turn becomes a span in a single trace, with the model, latency, cost, tokens and the exact input and output recorded on every span. The vendor states budgets and rate limits can be set per key, per customer or org-wide, with warnings as they are approached and requests blocked before spend runs over. Outputs can be scored against a bar the customer sets, on a test set and in production. ISO 27001, SOC 2, GDPR and HIPAA compliance with a BAA available are self-declared, with no report, auditor, certificate date or SOC 2 Type published on the page checked. The platform is described as sitting behind 80 trillion or more tokens, and pricing starts free. No insurance, indemnity, liability cap, settlement mechanism, outcome-based pricing or tamper-evident logging claim appears anywhere on the page checked.