LangSmith vs Manifest
LangSmith
langchain.comManifest
manifest.buildSide by side
| Figure | LangSmith | Manifest |
|---|---|---|
| Price from | $39/mo | $19/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| Web | Yes | Yes |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 3 | 4 |
| Spec score · LLM Gateway Software | 9.2 (#1) | 9.0 (#4) |
| Spec score · LLM gateways | 9.3 (#2) | 9.4 (#1) |
| Data residency | Cloud data is hosted in GCP US or EU regions, while self-hosted data remains in the customer's VPC. | For the self-hosted version, routing and request data stay on the customer's servers except for documented telemetry and Autofix flows. |
| Integrations | Documented integrations cover OpenAI, Anthropic, Bedrock, Gemini, Mistral, LiteLLM, OpenTelemetry, CrewAI, Vercel AI SDK, PydanticAI, AutoGen and many other frameworks and providers. | Manifest connects API keys, paid subscriptions, local models, and custom endpoints; named local integrations include Ollama, llama.cpp, and LM Studio. |
| Observability | Its observability features include agent tracing, cost tracking, online LLM-as-judge and code evaluations, trajectory monitoring, and webhook or PagerDuty alerts. | Usage views show spending, selected models, token consumption and failed requests for each harness. |
| Retention | Base traces are retained for 14 days and extended traces for 180 days at an additional charge. | Cloud request recordings are retained for 7 days on Free and 365 days on Pro. |
| Security | LangSmith's trust center lists SOC 2 Type II, ISO 27001:2022, GDPR and HIPAA compliance. | Manifest states that data in transit uses TLS, passwords are hashed, and Gateway provider credentials are encrypted with AES-256-GCM. |
| Self-hosting | Enterprise customers can run LangSmith self-hosted or hybrid on Kubernetes in AWS, Google Cloud or Azure. | Docker installation runs the full gateway stack locally without requiring Node.js and starts a dashboard on port 2099. |
| Support | The Developer plan includes community support, and the Enterprise plan lists a support SLA. | Free includes community support through Discord, Pro includes basic platform and billing support, and Enterprise includes dedicated Slack and email support. |
| What it does | LangSmith is LangChain's framework-agnostic platform for observing, evaluating and deploying AI agents. | Manifest is an open-source LLM gateway that routes AI-agent requests across providers, applies fallbacks, repairs failed requests and tracks inference costs. |
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.
Manifest
Manifest is an open-source LLM gateway for routing model requests, switching providers, repairing certain failures, and tracking inference spending. It provides one endpoint compatible with OpenAI and Anthropic models and subscriptions. When a provider goes down, fallback routing retries through another provider. Autofix repairs malformed requests and resends them when retries alone cannot resolve the error. Observability shows spending by harness, which models handled requests, and what failed. Manifest connects API keys, paid subscriptions, local models, and custom endpoints, including Ollama, llama.cpp, and LM Studio. The self-hosted gateway runs with Docker, works offline, requires no account, and supports amd64 and arm64. Self-hosted routing and request data remain on customer servers except documented telemetry and Autofix flows. The Cloud Free plan allows 10,000 routed requests per calendar month and cannot reach local models on the user's machine. Free includes unlimited self-hosted use; Pro costs $19 a month with unlimited Cloud requests and 365-day dashboard retention.