Langfuse vs Convex

Langfuse

Convex

Langfuse · 16 features

• Annotation Queues — Human reviewers rate traces. Unlimited on Pro+.
• Dashboards — Aggregate metrics, cost, quality across projects.
• Datasets — Curate test sets from production traces. Run experiments.
• EU Cloud Region — GDPR-compliant hosting in EU.
• Evaluations — LLM-as-judge, manual scores, custom model-graded evaluators.
• LLM Cost Tracking — Automatic cost calculation per provider/model.
• OpenTelemetry Native — OTel SDK → Langfuse endpoint works out of box.
• Playground — Test prompts + models + variables live.
• Prompt Management — Version, tag, label prompts. Reference from code by label.
• Public API — Full REST API for ingest, query, prompt management.
• Python @observe decorator — One-line decorator to trace any function.
• Self-Hosting — Docker Compose + k8s Helm chart.
• Sessions — Group related traces (conversations, agent runs).
• Tracing — Capture every LLM call, tool call, nested span with inputs/outputs/cost.
• Users Tracking — Segment traces by user ID, track per-user cost.
• Webhooks — Subscribe to trace completion events.

Convex · 18 features

• Actions — Non-deterministic functions for external I/O (fetch, AI APIs, email). Cannot rea…
• Authentication — Convex Auth (built-in) or BYO provider (Clerk, Auth0, Kinde, WorkOS). ID tokens …
• Convex Agents — AI agent framework with durable memory, threads, tool use. Works with OpenAI / A…
• Convex Auth — First-party auth library: passwords, magic links, OAuth, phone — stored in your …
• Convex Components — Reusable backend modules (rate limiter, workflow, aggregate, action-retrier, etc…
• Cron Jobs — Recurring schedules defined in convex/crons.ts. UTC, cron-style patterns.
• Durable Workflows — Long-running multi-step workflows with retries and at-least-once guarantees.
• Exception Reporting — Auto-capture errors to Sentry, Axiom, Datadog.
• File Storage — Upload/download via storage API. Returns storage IDs referenced in documents.
• Full-Text Search — BM25 search index on table fields. withSearchIndex query helper.
• HTTP Actions — Expose public HTTP endpoints for webhooks, OAuth callbacks, third-party integrat…
• Log Streams — Stream function logs to Axiom, Datadog, Sentry. Pro+.
• Mutations — Transactional write functions. All reads + writes in one mutation are ACID; conf…
• Preview Deployments — Every Git branch gets its own isolated deployment. Integrates with Vercel/Netlif…
• Queries — Deterministic read-only TS functions. Automatically cached and re-run when under…
• Real-Time Subscriptions — useQuery auto-subscribes; server invalidates when data a query read changes. No …
• Scheduler — schedule.after / schedule.at — enqueue functions to run later. Durable, survives…
• Vector Search — Native vector index on tables. withIndex + filter fields. Up to 4096 dims.