LangSmith vs Cal.com
LLM observability, testing & evaluation — by LangChain
vs. Open-source scheduling infrastructure — the self-hostable Calendly alternative
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
Cal.com
Free (Cloud)
$0. 1 user. Unlimited event types. Unlimited meetings. Cal branding.
Free
Self-Hosted (OSS)
Free forever. AGPL-3.0. Docker/K8s deploy. Full feature parity with cloud.
$0 base (usage-based)
Teams
$12/user/mo. Round-robin, collective events, routing forms, Cal Video, Workflows.
$12/mo
Organizations
$37/user/mo. SSO, advanced routing, dashboards, analytics, dedicated support.
$37/mo
Enterprise
Custom. SAML, HIPAA, dedicated deployments, security reviews.
Custom
Free-tier quotas head-to-head
Comparing developer on LangSmith vs free on Cal.com.
| Metric | LangSmith | Cal.com |
|---|---|---|
| No overlapping quota metrics for these tiers. | ||
Features
LangSmith · 14 features
- Alerts — Threshold alerts on latency, cost, eval metrics.
- Annotation Queues — Human-review workflows for trace quality rating.
- Custom Dashboards — Aggregate metrics dashboards per project/tag.
- Datasets — Collect examples → use as eval sets or training data.
- Evaluations — LLM-as-judge, embedding similarity, custom Python evaluators, offline batch eval…
- LangChain Integration — Auto-trace any LangChain/LangGraph run with env var.
- LangGraph Integration — First-class trace + eval for LangGraph agents.
- LLM Tracing — Automatic trace every LLM call + tool call + chain step.
- OpenTelemetry Export — Export traces as OTLP to Datadog/Honeycomb/etc.
- Playground — Test prompts + models inline before deploying.
- Prompt Canvas — Visual prompt editor with live test + eval.
- Prompt Hub — Public + private prompt library with versioning.
- Self-Hosted (Enterprise) — Docker + k8s deployment in your infra.
- Threads + Sessions — Group traces into conversational sessions.
Cal.com · 16 features
- Availability — Multiple schedules per user.
- Buffer Time — Padding between meetings.
- Cal Video — Built-in video conferencing.
- Embed — Inline/popup/floating-button embeds.
- Event Types — One-on-one, group, collective, round-robin.
- Insights Dashboard — Booking trends + team analytics.
- Paid Bookings — Stripe integration for paid appointments.
- Platform API — Embed scheduling in your SaaS.
- Recurring Events — Weekly/monthly recurring bookings.
- Round-Robin — Distribute bookings across team.
- Routing Forms — Route leads by answers.
- Self-Host — Deploy to your infra.
- SSO — SAML + OIDC.
- Timezone Detection — Auto-detect viewer timezone.
- Webhooks — Outbound events.
- Workflows — Automated email/SMS reminders.
Developer interfaces
| Kind | LangSmith | Cal.com |
|---|---|---|
| CLI | LangSmith CLI | cal CLI (self-host) |
| SDK | langsmith-js, langsmith-python | @calcom/embed-react |
| REST | LangSmith REST API | Cal.com REST API v2, Platform API (embed in SaaS) |
| MCP | LangSmith MCP | — |
| OTHER | LangSmith Dashboard | Cal.com Dashboard, Cal.com Webhooks |
Staxly is an independent catalog of developer platforms. Some links to LangSmith and Cal.com 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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