Alternatives
10 best LangSmith alternatives
Tools that cover the same task as LangSmith (code), ranked by how completely their pricing, free tier and API access are documented. Checked Oct 4, 2026.
- LangSmith starts at
- $39/mo
- Free plan
- Free plan
- API
- API available
- 01
Langfuse
Langfuse is an open-source LLM engineering platform for tracing, evaluating, and improving AI agents with collaborative debugging and metrics. Langfuse Cloud offers hosted Hobby, Core, and Pro tiers metered in observability units.
Best for: AI engineers who need open-source-friendly observability and eval workflows without building tooling in-house.
- 02
Mem0
Mem0 provides persistent memory infrastructure for AI agents and applications so context survives across sessions, users, and agents. The platform offers hosted plans with SDK integration plus open-source options for developers building production agents that need durable recall.
Best for: Agent builders and app teams that need hosted memory layers with defined add and retrieval quotas.
- 03
Voker
Voker is an analytics platform for AI agents in production, capturing intents, corrections, and resolutions from live conversations. SDKs wrap popular LLM providers so teams can monitor agent quality without digging through raw logs.
Best for: Product and engineering teams shipping customer-facing AI agents who need usage analytics and optimization signals.
- 04
Freestyle
Freestyle provides full Linux VMs purpose-built for long-running AI agents with millisecond startup, live cloning, pause/resume, nested Docker, and custom networking. Developers use the VMs for coding agents, browser automation, and containerized workloads.
Best for: Teams building autonomous agents that need persistent Linux environments, previews, and Docker inside the VM.
- 05
Deno Deploy
Plans scale request quotas, egress, custom domains, and collaboration features for hobby projects through enterprise deployments.
Best for: Developers and platform teams building on Deno who need managed edge hosting with optional sandbox and subhosting add-ons.
- 06
Laminar
Laminar is an open-source agent observability platform that captures LLM calls, tool calls, sub-agents, costs, and tokens, then surfaces failures through Signals and clustered failure modes. Hosted plans add retention, data limits, and support tiers for teams shipping production agents.
Best for: Engineering teams running AI agents who need trace visibility, automatic failure detection, and hosted retention without building observability in-house.
- 07
PropelAuth
PropelAuth provides authentication and org management built for B2B and AI-native products. The platform covers hosted login UIs, SAML and enterprise SSO, RBAC, API keys, and MCP authentication so teams can ship secure multi-tenant apps faster.
Best for: B2B SaaS and AI-native companies that need multi-tenant auth, enterprise SSO, and org management without building it in-house.
- 08
Infisical
Infisical is a security platform for developers and AI agents covering secrets management, certificate management, and privileged access. Cloud plans scale by identities with integrations, rotation, SSO, and enterprise controls for larger organizations.
Best for: Engineering teams and agent builders needing centralized secrets, certificates, and privileged access with SSO and audit trails.
- 09
Letta
Letta is an AI research lab and product company building stateful agents whose memory and capabilities evolve over time, originating from MemGPT research. It ships Letta Agent software, a CLI, and cloud plans for individuals, teams, and API developers.
Best for: Engineers and teams building long-horizon coding or workflow agents that need durable memory and sandboxed execution.
- 10
Lamatic AI
Lamatic AI is agentic middleware for teams to design, deploy, and optimize generative AI applications. Its visual builder, serverless deploy layer, and optimization tooling connect to hundreds of models and integrations for production agent workflows.
Best for: Product and engineering teams shipping GenAI features who want a visual builder with serverless deploy and observability without rebuilding infrastructure.
LangSmith alternatives: common questions
What is the best free alternative to LangSmith?
Langfuse has an ongoing free plan. Hobby cloud plan free with no credit card required Free plans change, so check the vendor before relying on one.
What is the cheapest LangSmith alternative?
Mem0 has the lowest listed starting price at $19/mo, compared with $39/mo for LangSmith.
Which LangSmith alternatives have an API?
Langfuse, Mem0, Freestyle, PropelAuth, Infisical mention API or developer access.