The rows worth reading.
LangSmith is the best tool if your entire stack is LangChain/LangGraph and your team is comfortable with its per-seat pricing. Outside that ecosystem it becomes friction-heavy — no auto-discovery, poor UX for CrewAI or AutoGen agents, and no AI-powered cost optimization. Zespan is built agent-first and works across every major framework from day one.
| Zespan | LangSmith | |
|---|---|---|
| Free tier | 10K traces/month | 5K traces/month |
| Starting price | $39/month | $39/seat/month |
| Framework support | Any framework + OTel | Best for LangChain/LangGraph |
| Agent auto-discovery | 2 lines, zero config | Not available |
| Multi-agent delegation graph | Limited (LangGraph only) | |
| Agent health scoring | A–F composite score | Not available |
| LLM-as-judge auto-evals | 12 templates, automatic | Manual only |
| AI cost optimizer | 30-day forecast + recs | Not available |
| Natural language query | ZespanPilot NLQ | Not available |
| Guardrails | 7 types, pre/post | Not available |
| Incident management | Full state machine | Not available |
| OpenTelemetry native | OTLP/HTTP endpoint | Partial |
Which one fits
Pick Zespan when
Your agents span multiple frameworks — CrewAI, AutoGen, Google ADK, custom.
You want cost forecasting, AI optimization recommendations, and anomaly detection.
You need guardrails, PII redaction, or runtime safety in production.
You want an AI copilot (ZespanPilot) for querying observability data in plain English.
You're evaluating at the team/org level and don't want per-seat pricing.
Pick LangSmith when
Your stack is 100% LangChain or LangGraph and you want the deepest native integration.
You want LangGraph state diffs between graph nodes — LangSmith's unique differentiator.
Your team already has LangSmith in its workflow and switching cost outweighs the gaps.
Common questions
Does Zespan support LangChain?
Yes. Zespan ships a drop-in LumiqCallbackHandler for LangChain and LangChain.js. It traces every chain step, agent reasoning, and tool call — the same way LangSmith does, but with the full Zespan feature set on top.
How does Zespan handle multi-framework teams?
Zespan supports LangChain, CrewAI, AutoGen, Google ADK, LlamaIndex, Vercel AI SDK, and PydanticAI out of the box — plus any OpenTelemetry-instrumented framework via the native OTLP/HTTP endpoint. One dashboard for your whole agent stack.
Is Zespan more expensive than LangSmith?
LangSmith starts at $39/seat/month. Zespan starts at $39/month flat for the Solo plan (one seat). For teams of 3+, Zespan's Pro plan at $149/month (10 seats) is typically cheaper than LangSmith's per-seat model.
Can I migrate from LangSmith to Zespan?
Yes. Replace LangSmith's callback or OTEL exporter with Zespan's drop-in equivalent. For LangChain apps, swap LangSmithTracer for LumiqCallbackHandler. Setup takes under 5 minutes.