Hexel vs LangSmith
Hexel
hexelstudio.com
LangSmith
langchain.comSide by side
| Figure | Hexel | LangSmith |
|---|---|---|
| Price from | Free | $39/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| API | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 3 | 3 |
| Spec score · AI Agent Platforms | 7.6 (#42) | 9.0 (#4) |
| Spec score · AI Agent Observability Tools | 7.7 (#24) | 9.1 (#4) |
| Founded | 2024 | 2023 |
| Integrations | The home page lists LangChain, LlamaIndex, CrewAI, AutoGen, OpenAI, Anthropic, Vercel AI, Pydantic AI, Temporal, Kubernetes, Python, and TypeScript as part of the agent stack it works with. | Documented integrations cover OpenAI, Anthropic, Bedrock, Gemini, Mistral, LiteLLM, OpenTelemetry, CrewAI, Vercel AI SDK, PydanticAI, AutoGen and many other frameworks and providers. |
| Observability | Hexel records plans, decisions, and tool calls as trace graphs, attributes compute spend by fleet, task, and team, and supports replay of runs. | Its observability features include agent tracing, cost tracking, online LLM-as-judge and code evaluations, trajectory monitoring, and webhook or PagerDuty alerts. |
| Security | Hexel says data is encrypted in transit with TLS 1.2+ and at rest with AES-256 across every plane. | LangSmith's trust center lists SOC 2 Type II, ISO 27001:2022, GDPR and HIPAA compliance. |
| Support | Scale includes priority support, while Enterprise includes solutions engineering and a dedicated SLA. | The Developer plan includes community support, and the Enterprise plan lists a support SLA. |
Plans
In their own words
LangSmith
LangSmith is a commercial agent-engineering platform for building, evaluating, deploying, monitoring, and improving AI agents. It supports offline evaluations on curated datasets and real-time scoring of production interactions. Evaluation methods include human review, heuristic checks, LLM-as-judge evaluators, pairwise comparisons, and custom Python or TypeScript evaluators. Annotation queues route runs to subject-matter experts for feedback that can calibrate evaluations, improve prompts, or augment datasets. The Playground compares prompt versions or model providers, and LangSmith chat can auto-improve prompts. Observability includes agent and retrieval tracing, token and general cost tracking, trajectory monitoring, online evaluations, and webhook or PagerDuty alerts. Traces can arrive through SDKs or an API from LangGraph, custom Python, or other stacks; SDKs are listed for Python, TypeScript, Go, and Java. Hosting ranges from cloud to hybrid and self-hosted Enterprise options. The Developer plan costs nothing, Plus costs $39 a month, and Enterprise pricing is custom.