Staxly

LangSmith vs Inngest

LLM observability, testing & evaluation — by LangChain
vs. Durable functions + event-driven workflows for modern apps

LangSmith websiteInngest website

Pricing tiers

LangSmith

Developer (Free)
Free forever. 5,000 traces/month. 14-day retention. 1 seat. Basic evaluations.
Free
Plus
$39/seat/month. 10k base traces included ($2.50 per 1k overage). Full evaluations, custom dashboards, email support.
$39/mo
Enterprise
Custom. Self-host option, SSO, custom retention, dedicated support.
Custom
LangSmith website

Inngest

Free
$0. 50K steps/mo + 1K concurrent executions. 7-day log retention. 1 environment.
Free
OSS (self-host)
Free forever. Inngest Dev Server + self-hosted Inngest runtime. Apache 2.0.
$0 base (usage-based)
Starter
$20/mo. 250K steps/mo. 5K concurrency. 14-day retention. 3 envs.
$20/mo
Pro
$75/mo. 1M steps/mo. 10K concurrency. 30-day retention. Priority support.
$75/mo
Enterprise
Custom. SSO, HIPAA, dedicated clusters, self-host with Inngest Enterprise.
Custom
Inngest website

Free-tier quotas head-to-head

Comparing developer on LangSmith vs free on Inngest.

MetricLangSmithInngest
No overlapping quota metrics for these tiers.

Features

LangSmith · 14 features

  • AlertsThreshold alerts on latency, cost, eval metrics.
  • Annotation QueuesHuman-review workflows for trace quality rating.
  • Custom DashboardsAggregate metrics dashboards per project/tag.
  • DatasetsCollect examples → use as eval sets or training data.
  • EvaluationsLLM-as-judge, embedding similarity, custom Python evaluators, offline batch eval
  • LangChain IntegrationAuto-trace any LangChain/LangGraph run with env var.
  • LangGraph IntegrationFirst-class trace + eval for LangGraph agents.
  • LLM TracingAutomatic trace every LLM call + tool call + chain step.
  • OpenTelemetry ExportExport traces as OTLP to Datadog/Honeycomb/etc.
  • PlaygroundTest prompts + models inline before deploying.
  • Prompt CanvasVisual prompt editor with live test + eval.
  • Prompt HubPublic + private prompt library with versioning.
  • Self-Hosted (Enterprise)Docker + k8s deployment in your infra.
  • Threads + SessionsGroup traces into conversational sessions.

Inngest · 14 features

  • AgentKitBuild AI agents as durable Inngest functions.
  • Auto RetriesConfigurable retries with exponential backoff.
  • Concurrency ControlsPer-function and per-user concurrency limits.
  • Cron TriggersScheduled functions via cron syntax.
  • DebounceCoalesce rapid-fire events into one execution.
  • Dev ServerLocal Inngest runtime for dev.
  • Durable Stepsstep.run, step.sleep, step.waitForEvent.
  • Event SystemTyped events with schemas.
  • Fan Out / BatchingProcess many events in parallel with batch control.
  • Priority LanesRoute premium customers to faster execution.
  • Rate LimitingThrottle events per key.
  • RealtimeStream function output to clients.
  • ReplayRe-run past functions with new code.
  • Self-HostOSS runtime — run your own Inngest.

Developer interfaces

KindLangSmithInngest
CLILangSmith CLIinngest-cli (dev server)
SDKlangsmith-js, langsmith-pythoninngestgo, inngest (Python), inngest (TS/Node)
RESTLangSmith REST APIInngest REST API
MCPLangSmith MCPInngest MCP
OTHERLangSmith DashboardInngest Cloud Dashboard
Staxly is an independent catalog of developer platforms. Some links to LangSmith and Inngest may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.

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