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Respan

LLM engineering platform for agent observability, evals, and prompt optimization.

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Intro

What is Respan?

Respan (formerly known as Keywords AI) is an advanced LLM engineering platform designed for building, monitoring, and scaling AI agents. Acting as a unified AI gateway, it unifies crucial developer workflows such as LLM observability, automated evaluations (evals), and prompt optimization. Positioned alongside competitive tools like LiteLLM and OpenRouter AI, Respan offers developers the signals and controls needed to trace agent behavior, manage over 500 models, and optimize prompts directly within production traffic.

Respan at a glance
Free, Team from $199/mo58K monthly visitsHas free access

Category

AI MonitorAI Developer Tools
Best For

Best Respan use cases by task, role, industry, and platform

These use cases show where Respan fits best, ranked by fit score before popularity or pricing.

LLM ObservabilityMonitor, trace, and analyze large language model outputs to debug errors, track costs, and improve prompt performance.100LLM GatewayRoute API requests, manage API keys, track costs, and switch between different language models through a single unified interface.100AI Agent BuildingDesign, configure, and deploy automated digital assistants to handle repetitive workflows and connect multiple software applications.95LLM EvaluationAssess model outputs, benchmark performance metrics, test prompts, and validate responses to ensure accuracy across specific use cases.95Performance OptimizationAnalyze existing code, databases, and system configurations to identify bottlenecks and accelerate application response times.85AutomationConnect recurring steps, prepare rules, summarize outcomes, and reduce manual work across routine processes.75
Pricing

Respan Pricing Plans

Compare Respan free options, Respan paid pricing plans, and usage notes before you choose the best way to use this AI tool in 2026.

Free, Team from $199/mo

$0

For getting started. Includes full platform access, 100k logs, 1k scores, 5 datasets, 2 evaluators, 5 prompts, and a 7-day data retention period.

$199 per month

For startups and growing teams. Everything in Pro plus unlimited datasets, evaluators, and prompts, 10k scores, 30-day retention, private Slack channel, and SOC 2 report. Billed yearly.

Contact us

For large organizations. Everything in Team plus custom packages, volume discounts, custom SLAs, dedicated support engineer, HIPAA BAA, and self-hosted deployment options.

Pricing updated:Jun 12, 2026

Features

Respan AI Features

Agent Tracing: End-to-end capture of prompts, tool calls, and execution paths.Automated & Custom Evaluations: Combine human review, code checks, and LLM judges.Prompt Optimization: Version control, Jinja templates, and comparative experiments against real baselines.Unified AI Gateway: Single endpoint providing routing, caching, and fallback logic across 500+ models.Real-Time Monitoring: Custom dashboards with over 80 graph types to track quality, latency, and cost.
Pros & Cons

Respan Pros and Cons

Pros

  • Excellent developer and user experience (DX/UX) that is easy to integrate.
  • Comprehensive all-in-one suite combining logging, evals, proxying, and monitoring.
  • Enterprise-grade security and compliance including ISO 27001, SOC 2, GDPR, and HIPAA.
  • High reliability capable of scaling to hundreds of millions of API calls and trillions of tokens.

Limitations

  • The Pro (Free) plan limits log retention to only 7 days.
  • Advanced features like HIPAA BAA compliance require a paid add-on or enterprise plan.

Respan FAQ

Keywords AI has rebranded and is now operating under the name Respan, expanding its capabilities as a comprehensive LLM engineering and observability platform.

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