Alternatives to LangSmith

6 editor-selected alternatives · LangSmith overview →

source: tools.alternatives · stored order · active records only; review scores are annotations and never change membership or order

A directional evidence panel appears only when the substitute rationale, trade-offs, sources, and verification date have been recorded. Older selections without that panel remain visible but are unclassified under the new evidence contract.

Composio

82/100open sourcefreemiumexplicit relation

Composio connects AI agents to 1,000+ app toolkits with managed auth, delegated user connections, sessions, tool search, MCP gateway support, CLI workflows, and sandboxed workbench execution. It targets developers building Claude, Codex, Cursor, LangChain, CrewAI, OpenAI Agents SDK, and custom agent workflows that need authenticated business actions without hand-rolling every API integration.

Composio provides tool integrations and execution environments for AI agents and LLMs. It features a Free plan with 100,000 monthly tool calls and 50,000 triggers for up to 3 team members. The Pro plan starts at $29/month with scaling overages ($4/1k extra calls), and Enterprise tiers include custom KMS credential management and SLAs.Review →

Steel

open sourcefreemiumexplicit relation

Steel is an open-source browser API purpose-built for AI agents, providing managed headless browser sessions with anti-bot bypass, proxy rotation, CAPTCHA solving, and session persistence. It handles the infrastructure layer that browser automation agents like Browser Use and Stagehand run on top of. Self-hostable or available as a cloud service. Over 6,000 GitHub stars.

Open-source browser sandbox (Apache-2.0) with $0 self-hosted deployment. Steel Cloud offers a Free tier with 100 browser hours/month ($30 starting credits). Paid usage is metered at ~$0.08/browser hour, with CAPTCHA solving starting at $1/1k solves and residential proxy bandwidth from $6/GB. Enterprise plans provide dedicated infrastructure, custom concurrency limits, and 24/7 SLA.

Agno

82/100open sourceexplicit relation

Fast, lightweight Python framework for building multi-modal AI agents, formerly known as Phidata. Includes built-in memory, knowledge bases, tools, and reasoning capabilities with 40K+ GitHub stars. Designed for developers who want to build production-ready agents quickly with minimal boilerplate, supporting structured outputs and multi-agent coordination out of the box.

Agno (formerly Phidata) offers a free open-source framework under the MIT license for building multimodal AI agents. The managed production platform provides a Pro plan at $150/month (including 1 live connection) and custom Enterprise tiers.Review →

Braintrust

86/100freemiumexplicit relation

Braintrust is an AI observability and evaluation platform for tracing LLM applications, building datasets, running prompt/model experiments, scoring outputs and turning production feedback into regression tests. It fits teams that need repeatable quality gates for AI releases rather than one-off prompt demos.

Starter plan is free with unlimited users, $10 in credits, 1 GB data ingestion, 10,000 scores, and 14-day retention. Pro plan is $249/month including $249 in credits, 5 GB data ingestion, 50,000 scores, 30-day retention, and RBAC ($3/GB data and $1.50/1k score overages). Enterprise plan offers custom data retention, VPC/on-premise self-hosted options, and dedicated SLAs.Review →

TraceRoot

open sourcefreemiumexplicit relation

TraceRoot is a YC S25-backed open-source observability platform purpose-built for AI agents and LLM apps. It combines OpenTelemetry-compatible tracing with an agentic debugging runtime that reads your source code, correlates failures with recent commits, and proposes fix PRs automatically. BYOK support spans seven LLM providers; the entire stack runs self-hosted via Docker Compose, with TraceRoot Cloud available for managed deployments.

TraceRoot is a 100% free and open-source agent observability platform under Apache-2.0 that provides distributed tracing, token-efficient debugging, and self-healing analysis for autonomous agents.

Judgeval

89/100open sourceexplicit relation

Judgeval is the open-source post-building layer for AI agents from Judgment Labs, providing OpenTelemetry-based tracing, hosted and custom evaluation scorers, and online behavior monitoring for LLM-powered applications. Instrument any function with a single decorator, score live production traffic against faithfulness and instruction-adherence checks, and feed real-world failures back into reinforcement learning or supervised fine-tuning loops.

Judgeval is an open-source Python SDK (Apache-2.0) for AI agent evaluation and tracing. Judgment Labs offers hosted enterprise agent behavior monitoring and evaluation platform access via custom quotes.Review →

Open-source LangSmith alternatives

Composio, Steel, Agno, TraceRoot, Judgeval — see all open-source developer tools.

Free LangSmith alternatives

Composio, Steel, Braintrust, TraceRoot offer a free plan or free tier.

More Testing & QA tools

same category, not editor-selected alternatives — see how LangSmith compares →

OpenLITOpenLIT is an open-source AI engineering platform that provides OpenTelemetry-native observability for LLM applications. It combines distributed tracing, evaluation, prompt management, a secrets vault, and GPU telemetry in a single self-hostable stack. With 50+ integrations across LLM providers and frameworks, it lets teams monitor AI applications using their existing observability backends like Grafana, Datadog, or Jaeger.MCP InspectorMCP Inspector is the official interactive developer tool from the Model Context Protocol team for testing, debugging, and validating MCP servers. It provides a visual interface to inspect available tools, test transport configurations, export configs for different clients, and verify protocol compliance during MCP server development.PlaywrightCross-browser E2E testing framework by Microsoft supporting Chromium, Firefox, and WebKit with one API. Features auto-waiting, tracing with timeline/screenshots/DOM snapshots, codegen for recording tests, and parallel execution. Component testing for React, Vue, Svelte. Built-in API testing, network mocking, and mobile emulation. Known for reliability and speed vs Selenium/Cypress. 70K+ GitHub stars, rapidly becoming the E2E standard.GrafanaGrafana is the leading open-source platform for monitoring and observability visualization. It connects to virtually any data source — Prometheus, Elasticsearch, InfluxDB, PostgreSQL, CloudWatch, Datadog, and 150+ others — to create beautiful, interactive dashboards. Used by millions of users at companies like Bloomberg, JPMorgan, eBay, and PayPal. Grafana Cloud offers a fully managed experience with generous free tier. The CNCF ecosystem standard for metrics visualization.LatitudeLatitude is an agent observability platform for teams that need to inspect LLM traces, conversations, issues, and evaluation feedback in one workflow. Its public repo and docs position it as a Sentry-style monitor for AI agents, with semantic search, issue detection, annotations, MCP-assisted fixes, and cloud or self-hosted deployment paths for production debugging.SentrialSentrial is a YC W26-backed monitoring platform for AI agent reliability in production. It semantically detects loops, hallucinations, tool misuse, and user frustration in real-time, then diagnoses root causes and recommends fixes. The platform claims 70% MTTR reduction via automated remediation including rollback, model retraining triggers, and webhooks. Sentrial positions itself as the Datadog for teams deploying autonomous AI agents at scale.DatadogDatadog is a cloud observability and security platform that unifies metrics, traces, logs, RUM, synthetics, APM, and security signals. Current pricing pages list 1,000+ integrations for Infrastructure Monitoring, with Pro from $15/host/month and Enterprise from $23/host/month when billed annually.DeepEvalDeepEval is an Apache-2.0 Python framework for evaluating LLM apps, RAG systems, agents, MCP workflows, and safety behavior with repeatable test cases. It works locally and in CI/CD, then connects to Confident AI for hosted reports, observability, red teaming, and governance when teams need shared evidence instead of ad-hoc prompt reviews and manual QA.PostHogPostHog is an open-source product and data tools platform for analytics, session replay, feature flags, experiments, surveys, error tracking, web analytics, data warehouse, CDP and LLM observability workflows. It suits developer-led teams that want one integrated product OS instead of many separate tools.

LangSmith head-to-head

FAQ

Which LangSmith alternative is listed first?

Composio is first in the editor-selected list of 6 LangSmith alternatives and carries an editorial review score of 82/100. The stored order is editorial; review scores do not determine membership or position.

Are there open-source LangSmith alternatives?

Yes — Composio, Steel, Agno, and more are open source.

Are there free LangSmith alternatives?

Yes — Composio, Steel, Braintrust, and more offer a free plan or free tier.