Zespan is an AI agent observability and engineering platform. It traces every agent decision, tool call, handoff, and delegation in production. It also provides prompt versioning, built-in LLM-as-judge evaluations, guardrails, cost optimization, and an AI ops assistant called ZespanPilot.

How do I instrument my AI agent with Zespan?

Zespan requires 2 lines of code. Import zespan and call zespan.init({ apiKey: process.env.LT_KEY }). This auto-patches OpenAI, Anthropic, Gemini, Bedrock, and Mistral. For framework-level tracing, add one handler: ZespanCallbackHandler for LangChain, ZespanCrewAIListener for CrewAI, or ZespanADKHandler for Google ADK.

Does Zespan support prompt versioning?

Yes. Zespan includes prompt management with versioning, a playground for iteration, and A/B testing to compare prompt versions against each other in production.

What evaluations does Zespan support?

Zespan ships 12 built-in LLM-as-judge evaluation templates including faithfulness, relevance, toxicity, groundedness, and more. Evaluations run automatically on every trace with no custom scoring functions required.

How does Zespan compare to Langfuse?

Zespan is agent-native: every span carries agent identity, delegations are first-class trace events, and an agent map is built automatically. Langfuse was built for LLM pipelines and extended to agents later. Zespan also ships 12 built-in eval templates (Langfuse has none), includes an AI cost optimizer, and ZespanPilot for AI ops. Langfuse has open-source self-hosting; Zespan does not.

What is the free tier for Zespan?

The free tier includes 10,000 traces per month, 14-day retention, 2 projects, and 1 seat. No credit card required.

Compare

Zespan vs Arize

Zespan vs Arize — purpose-built for LLMs vs adapted from ML.

Arize is a mature ML observability platform that expanded into LLM monitoring. It's powerful for teams with existing Arize infrastructure and ML engineers who know the platform. For teams building AI agents with LLMs, Zespan offers faster setup, purpose-built agent features, and more accessible pricing for startups and scale-ups.

Capability comparison: Zespan vs Arize
Capability	Zespan	Arize
Setup time	< 5 min (2 lines)	Hours (platform config)
Built for	LLM agents from day one	ML, adapted for LLMs
Agent auto-discovery	✓ Zero config	Manual registration
Agent health scoring	✓ A–F composite	Not available
Multi-agent delegation graph	Yes	Partial
LLM-as-judge auto-evals	✓ 12 templates	Configurable
AI cost optimizer	✓ Forecast + recs	Not available
Guardrails	✓ 7 types, pre/post	Not available
Natural language query	✓ ZespanPilot NLQ	Not available
Incident management	✓ Full lifecycle	Not available
Startup/SMB pricing	✓ From $39/month	Enterprise pricing
OpenTelemetry native	Yes	Yes

Pick Zespan when…

You're a startup or scale-up — Zespan pricing starts at $39/month, not enterprise contract.
You want < 5 min setup with no platform configuration.
You need agent-first features: health scoring, delegation graphs, ZespanPilot.
You want cost forecasting, optimization recommendations, and anomaly detection.
You don't have ML engineers on staff — Zespan is built for software engineering teams.

Pick Arize when…

You're an enterprise already invested in Arize's broader ML platform.
You need ML model monitoring alongside LLM tracing in one platform.
Your team has Arize expertise and the switching cost exceeds the capability gap.

Frequently asked

Is Zespan suitable for enterprise teams?

Yes. Zespan offers SSO, RBAC (owner/admin/member/viewer roles), audit logs, GDPR compliance (Art. 15 and 17), and custom quotas on Team and Enterprise plans. Contact us for enterprise pricing.

How long does Zespan setup take compared to Arize?

Zespan takes under 5 minutes — install the SDK, add your API key, and wrap your LLM client. No platform configuration, no collector setup. Arize typically requires significant platform configuration before data flows.

Does Zespan support OpenTelemetry like Arize does?

Yes. Zespan has a native OTLP/HTTP endpoint that accepts standard OpenTelemetry spans from any OTel SDK or collector. No proprietary format required.

Try Zespan — free, no card needed

10K traces/month free. Setup takes under 5 minutes. See why teams switch from Arize.

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