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Respan for Developers

Log every LLM call, trace agent pipelines, and run quality evals — with two lines of code. No infra to build, no dashboard to maintain.

Proven at scale

Works with OpenAI, Anthropic, Gemini, Groq, LangChain, LlamaIndex, and 20+ integrations.

What you get

Everything you'd build yourself if you had the time — ready in minutes, free to start.

Debug production failures

Find the exact request that went wrong. See inputs, outputs, latency, and the full agent trace — searchable in seconds.

Trace agent pipelines

View every step of a multi-step agent: which tools were called, what data passed between steps, and where latency accumulated.

Track costs per request

See token usage and dollar cost for every call. Break down spend by model, feature, or user to find where money goes.

Run quality evals

Apply built-in evaluators (hallucination, relevance, toxicity) or write custom Python checks. Scores tracked over time.

Version prompts without deploys

Store prompts in Respan, pull at runtime via SDK. Edit, A/B test, and roll back from the dashboard — no redeploy needed.

Search and filter all logs

Full-text search across every request. Filter by user, model, cost, latency, status, or custom metadata tags.

Set up alerts

Threshold alerts for cost spikes, latency regressions, and error rate increases. Get notified before users do.

Export everything

Pull logs, traces, and eval results via REST API. Stream to S3, BigQuery, or any destination via webhooks.

How developers use Respan

Daily workflow

  • →Search logs by user ID to debug a reported issue
  • →Check the trace waterfall for slow agent steps
  • →Compare cost before and after a model change
  • →Review eval scores after a prompt update

Quality & evals

  • →Run hallucination checks on every production output
  • →Build eval datasets from real traffic, not synthetic examples
  • →Compare prompt variants with automated A/B scoring
  • →Track quality trends to catch regressions early

Ship & iterate

  • →Deploy prompt changes without code deploys
  • →Set cost alerts before LLM bills surprise you
  • →Export labeled data for fine-tuning workflows
  • →Instrument new features in minutes, not days

How it works

From zero to full observability in under 5 minutes. No infrastructure to deploy.

1

Install the SDK

pip install respan or npm install respan. One package, zero configuration.

→ SDK ready

2

Wrap your LLM client

Two lines of code. Wrap your OpenAI, Anthropic, or framework client. Every call is logged automatically.

→ Structured logs for every request

3

Search and debug

Find any request by content, user, cost, or metadata. Trace agent pipelines step-by-step.

→ Root cause identified in seconds

4

Evaluate quality

Run evaluators on production outputs: hallucination, relevance, coherence, or custom checks.

→ Quality scores per request and over time

5

Iterate and ship

Update prompts from the dashboard. Compare variants. Deploy changes without touching code.

→ Better outputs, shipped faster

By the numbers

<5 min

from signup to first log

2 lines

of code to instrument

100%

of requests captured

<80ms

P99 ingestion latency

Works with your stack

Model providers

  • OpenAI
  • Anthropic
  • Google Gemini
  • Groq
  • Mistral
  • Together AI
  • Azure OpenAI
  • AWS Bedrock
  • Any OpenAI-compatible endpoint

Frameworks

  • LangChain
  • LlamaIndex
  • Vercel AI SDK
  • Mastra
  • CrewAI
  • OpenAI Agents SDK

Languages

  • Python
  • TypeScript / JavaScript
  • Go
  • Ruby
  • Any language via REST API

Frequently asked questions

Frequently asked questions

Built for AI agents.
Break less.
Ship more.