Langtrace

Open-source LLM observability platform that traces calls to LLM APIs (OpenAI, Anthropic, etc.) and provides evaluation, cost tracking, and performance analytics.

Evaluated Mar 06, 2026 (0d ago) vcurrent
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⚙ Agent Friendliness
60
/ 100
Can an agent use this?
🔒 Security
82
/ 100
Is it safe for agents?
⚡ Reliability
78
/ 100
Does it work consistently?

Score Breakdown

⚙ Agent Friendliness

MCP Quality
--
Documentation
82
Error Messages
78
Auth Simplicity
90
Rate Limits
75

🔒 Security

TLS Enforcement
100
Auth Strength
80
Scope Granularity
70
Dep. Hygiene
82
Secret Handling
80

API key has no scope restrictions; self-hosted gives full data control

⚡ Reliability

Uptime/SLA
80
Version Stability
78
Breaking Changes
75
Error Recovery
78
AF Security Reliability

Best When

Building multi-model LLM applications and needing visibility into per-call costs, latency, and quality across providers.

Avoid When

Your LLM usage is simple single-provider with no evaluation requirements — basic logging suffices.

Use Cases

  • Auto-trace all OpenAI and Anthropic API calls to track token usage, latency, and costs
  • Evaluate LLM response quality with built-in and custom evaluators on production traces
  • Compare model performance across different LLM providers side-by-side using trace datasets
  • Alert on LLM latency spikes or cost anomalies with threshold-based monitoring
  • Export traces as datasets for fine-tuning or prompt optimization workflows

Not For

  • General application monitoring beyond LLM calls — use Datadog APM or Honeycomb
  • Self-hosted deployment with zero external data egress requirements (cloud mode required)
  • Real-time streaming trace analysis — traces are batched for ingestion

Interface

REST API
Yes
GraphQL
No
gRPC
No
MCP Server
No
SDK
Yes
Webhooks
No

Authentication

Methods: api_key
OAuth: No Scopes: No

LANGTRACE_API_KEY environment variable; one key per project

Pricing

Model: freemium
Free tier: Yes
Requires CC: No

Open source — can self-host with full features

Agent Metadata

Pagination
cursor
Idempotent
No
Retry Guidance
Not documented

Known Gotchas

  • Auto-instrumentation patches LLM client libraries at import time — import order matters; import langtrace before openai/anthropic
  • Cloud free tier 10K trace limit resets monthly but does not warn at 80% usage — monitor manually
  • Evaluation scores are computed async after trace ingestion — not available synchronously in response
  • Self-hosted requires PostgreSQL + ClickHouse for full feature parity — not just a single Docker container
  • SDK wrapping may add 5-20ms overhead to LLM calls — benchmark in latency-sensitive applications

Alternatives

Full Evaluation Report

Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Langtrace.

$99

Scores are editorial opinions as of 2026-03-06.

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Packages Evaluated
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Need Evaluation
173
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