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LangWatch

Open source · OSI-approvedStatus: unknownNew

Open-source agent observability, evals, and AI governance

LangWatch is an open-source observability and evaluation platform built for AI platform teams, covering LLM operations, coding-assistant usage, AI gateway routing, and AI governance in one place. Teams trace every agent run and model call, test agents with simulations and no-code evaluations, and watch company-wide AI spend and risk from a single dashboard.[1][2]

Quick verdict

Platform teams owning production AI benefit most. AI platform teams responsible for production agents and company-wide coding assistants benefit most from LangWatch. One open-core platform combines end-to-end tracing, simulation and no-code evaluations, an AI gateway with budgets, and governance views over every AI tool in the company. The constraint is operational and commercial shape: real use assumes engineers who own SDK instrumentation or a coding-assistant rollout, and advanced governance and enterprise controls sit in paid tiers. If you need evaluations plus gateway and governance in one open-source platform, choose LangWatch; if you need a larger integration catalog with prompt playground depth and region-pinned cloud hosting, compare Langfuse first.[1][2][3][4]

Key features

  • End-to-end tracing for agents and assistants End-to-end tracing for agents and assistants: trace every agent run and LLM call with hierarchical spans across chains, tools, retrieval steps, and users, fed by Python and TypeScript SDKs plus more than twenty integrations including OpenTelemetry.[1]

  • Scenario simulation tests Scenario simulation tests: create simulation tests for agents and voice agents that replay realistic multi-turn scenarios at temperature zero for deterministic results, instead of hand-checking chat transcripts.[1]

  • No-code evaluations with assertions No-code evaluations with assertions: build evals without code using assertion checks, RAG faithfulness and relevance metrics, and PII detection, runnable offline over datasets or online over production traffic.[1]

  • Datasets, annotation, and experiments Datasets, annotation, and experiments: collect production traces into versioned datasets, annotate them, and track experiments so prompt and model changes are compared rather than eyeballed.[1]

  • Versioned prompt management Versioned prompt management: manage versioned prompts inside the LLM operations workflow and deliver them through prompt-as-an-API, keeping prompt changes reviewable.[1]

  • Coding-assistant usage tracking Coding-assistant usage tracking: track company coding assistants launched from common editors and CLIs with per-session, per-PR, and per-team cost and duration analytics plus privacy controls over collected data.[1]

  • AI gateway with virtual keys and budgets AI gateway with virtual keys and budgets: route OpenAI and Anthropic traffic through one compatible endpoint with virtual keys, model routing and fallbacks, spending budgets, and credential rotation.[1][2]

  • Guardrails and AI governance Guardrails and AI governance: redact PII before it reaches models, set anomaly and cost rules with alerts, and keep an inventory of every AI tool in the company, including findings such as shadow Copilot Studio spend.[1][2][3]

Who will love it

  • Teams debugging agents in production: hierarchical traces with session, cost, and latency views isolate looping, failing-tool, and slow-step behavior across agent runs.[1]

  • Teams building evaluation loops: no-code assertions, scenario simulations, datasets with annotation, and experiment tracking turn one-off prompt tweaks into repeatable checks.[1]

  • Organizations governing company AI use: gateway budgets, PII guardrails, coding-assistant analytics, and a tool inventory give platform teams one place to control spend and risk.[1][2]

Who should avoid it

  • Non-technical teams wanting turnkey AI: SDK instrumentation, gateway routing configuration, and cloud or self-hosted setup assume engineers who own code and infrastructure.[1][2]

  • Budget-capped teams ignoring usage metering: cloud plans add usage-based credits above seat pricing with per-tier retention, so confirm metering before committing.[1]

  • Teams needing audited compliance depth: SOC 2 and GDPR posture is stated with DPA and questionnaire support, but regulated buyers should verify the current audit documents before treating this as a compliance decision.[1][2]

Alternatives and compatibility

Langfuse is the natural catalogue comparison to LangWatch: both cover OpenTelemetry tracing, evaluations, datasets, and experiment comparison for LLM and agent workloads.[1][2]

LangWatch fits teams that want evaluations plus gateway routing, coding-assistant analytics, and AI governance in one open-source platform, and can carry cloud usage spend or a self-hosted stack with paid enterprise tiers.[1][2][3][4]

Langfuse fits teams needing a larger documented integration catalog with prompt playground depth or region-pinned cloud hosting; non-technical teams should pick neither and choose a finished product instead.[1]

Questions worth asking

What is the best LangWatch alternative for non-technical users?

Neither LangWatch nor its closest catalogue comparison, Langfuse, suits non-technical users, since both assume engineers own SDK instrumentation and cloud or self-hosted setup. A non-technical team should choose a finished AI product for its task rather than any agent observability platform.[1][2][3]

Is LangWatch really no-code?

Mostly for analysis, not for setup. Once instrumented, trace inspection, no-code evaluations, dataset annotation, and gateway budgets are point-and-click, but SDK or OpenTelemetry instrumentation, gateway routing, and cloud or Docker and Helm setup still need engineering work.[1][2]

How much does LangWatch cost per month?

As checked October 2026, LangWatch Cloud lists a free Hobby tier with paid Pro, Team, and Enterprise plans plus usage-based credits that roll over, with unlimited seats, EU and US region selection, and dedicated support with an SLA on Enterprise. Confirm current pricing on langwatch.ai before budgeting, since credit metering and plan limits drive the bill.[1]

Can you self-host LangWatch?

Yes, on operator infrastructure with a one-command starter requiring only Node.js, plus Docker Compose and Helm chart paths for the open-core edition. The core is Apache 2.0 licensed with some enterprise features under a commercial license, so check the self-hosting guide for the configuration you need.[1][2]

Sources and editorial review

Source research. Reviewed on October 11, 2026. Written by Sanjib Sah. AI assisted; reviewed by a human editor.

We have not run or tested this product.

  1. LangWatch - The Open-Source Agent Observability Platform

    official · Observed October 11, 2026

    Official homepage: open-source agent observability platform for AI platform teams; end-to-end tracing, evals, prompt management, gateway, guardrails, datasets; customers Bolt, Siemens, autonomy; founded 2023; SOC 2 Type II; GDPR.

  2. LangWatch pricing

    official · Observed October 11, 2026

    Pricing lists a free Hobby tier with paid Pro, Team, and Enterprise plans, usage-based credits that roll over, unlimited seats, EU/US region selection, SSO/SAML and audit logs on Enterprise, dedicated support with SLA, and guardrails, PII redaction, and no-code evals on paid tiers. Open-core: Apache 2.0 core plus commercial EE.

  3. LangWatch documentation - Streamline Your Evaluations

    official · Observed October 11, 2026

    Docs introduction: no-code evals with assertions, RAG metrics, PII checks; scenario simulations for agents and voice agents at temperature 0; LLM Ops list (tracing, evals, datasets, experiments, prompt management, prompt-as-API); Python and TypeScript SDKs with 20+ integrations including OpenTelemetry.

  4. LangWatch self-hosting

    official · Observed October 11, 2026

    Self-hosting page: one-command starter, docker compose and helm chart paths for the open-core edition on operator infrastructure.

  5. langwatch/langwatch repository

    official · Observed October 11, 2026

    Repository page for langwatch/langwatch: public, Apache-2.0, 4.9k stars, 506 forks, 15 releases, 36 contributors, active October 2026 commits. README: platform for AI in production (LLM Ops, coding agents, gateway, governance); coding-agent tracking via npx for Claude Code, Codex, Copilot, OpenCode; OpenAI/Anthropic-compatible gateway with virtual keys, budgets, routing; MCP server; one-command self-host; MIT SDKs.

  6. Langfuse product record

    official · Observed October 11, 2026

    Published catalogue comparison: open-source LLM observability with OTel-native tracing, LLM-as-a-judge evals, datasets, experiments, prompt management, and Cloud plus self-hosted deployment.

Compared with these products

No explicit proprietary baseline is recorded.

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