Route, trace, evaluate, and monitor model and agent traffic through one engineering platform
Advisor score
Documented editorial evaluation
The decision
Respan earns a pilot for teams whose model traffic, evaluations, and prompts have outgrown separate dashboards and scripts. Use the free tier to prove trace quality and incident-time savings, keep a tested provider bypass, exclude sensitive fields by default, and grant production evaluators authority only after measuring false positives and false negatives.
Best for
Teams operating multiple model providers; Developers debugging production AI agents.
Choose something else if
Workloads that cannot send traces through a third party; Teams needing an evaluator to act as ground truth
Evidence
Editorial research pending · 8.2/10
Pricing checked
See current vendor pricing · Sep 9, 2026
Free access is available, with limits.
Yes. The Free plan includes the full platform within published log, score, prompt, evaluator, dataset, retention, and throughput limits.
Community choice
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Respan, formerly Keywords AI, combines a multi-model gateway with tracing, cost monitoring, prompt management, datasets, evaluations, alerts, and production controls.
Respan earns a pilot for teams whose model traffic, evaluations, and prompts have outgrown separate dashboards and scripts. Use the free tier to prove trace quality and incident-time savings, keep a tested provider bypass, exclude sensitive fields by default, and grant production evaluators authority only after measuring false positives and false negatives.
Mirror five percent of sanitized production traffic for two weeks, then route a reversible workload through Respan with direct-provider bypass available. Compare trace completeness, evaluator agreement with 300 expert labels, fallback correctness, cache safety, p50 and p95 latency, gateway and provider errors, cost attribution, PII masking, export quality, and recovery during an injected outage. Calculate platform cost per investigated failure and per accepted output.
Personal Recommendation
Respan earns a pilot for teams whose model traffic, evaluations, and prompts have outgrown separate dashboards and scripts. Use the free tier to prove trace quality and incident-time savings, keep a tested provider bypass, exclude sensitive fields by default, and grant production evaluators authority only after measuring false positives and false negatives.
Try the recommendation
Gateway, traces, evaluations, and prompts in one platform
Overall Score
Editorial Review Framework
Overall Score
8.2
Ease of Use
8.0
AI Quality
8.2
Features
8.6
Speed
8.0
Integrations
8.4
Value for Money
8.0
Customer Support
7.6
Learning Curve
7.4
Recommended Because…
Gateway, traces, evaluations, and prompts in one platform
Scores use a 0-10 editorial scale: 9–10 exceptional, 8–8.9 strong, 7–7.9 capable with material tradeoffs, 6–6.9 limited fit, and below 6 not recommended. Scores publish only when a documented evaluation supports them.
Reusable trial worksheet
Turn this review’s buyer test into evidence. Your entries autosave only in this browser and are never added to shared shortlist links.
Confirm the tool meets every must-have workflow and stakeholder requirement.
Review starting point: Teams operating multiple model providers; Developers debugging production AI agents; Organizations unifying gateway, prompts, evals, and spend
Run the same representative work you would use in production; do not score a polished demo.
Review starting point: Complete three to five representative tasks with known acceptable outcomes and compare them with your current process.
Calculate the effective cost per accepted result, including usage, review, corrections, and required add-ons.
Review starting point: Respan lists a $0 Free plan with 100,000 logs, 1,000 scores, five datasets, two evaluators, five prompts, seven-day retention, and one workspace. Team is $199 per month when billed annually and adds unlimited datasets, evaluators, and prompts, 30-day retention, five members, and private Slack support. Extra usage is listed at $8 per 100,000 logs and $1 per…
Define an acceptance threshold, test known answers and edge cases, and record every correction.
Review starting point: Editorial quality signals: features 4.3/5; AI quality 4.1/5. Validate these signals in your own work.
Verify what data enters the product, who can access it, how long it is retained, and whether it trains models.
Review starting point: Use approved low-risk data first. Check roles, consent, deletion, subprocessors, model-training settings, and the contract—not only the marketing page.
Test the real handoffs, permissions, failure states, and export path your team depends on.
Review starting point: OpenAI SDK, Vercel AI SDK, LangChain, LlamaIndex, Mastra, OpenTelemetry
Record training, governance, reliability, accessibility, ownership, and change-management risks before rollout.
Review starting point: Creates a central traffic and telemetry dependency; Team price requires annual billing; Judges and fallbacks need independent validation
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Evaluation
Research-based
Price posture
From $0/month
Reviewed
2026-09-09
No authentic product screenshot is published for this review. DiscoverAI does not use generated interface images as product evidence.
Editorial freshness
Pricing and material product claims were checked September 9, 2026.
Community evidence
Structured, editor-moderated experience—not star ratings. This complements our independent review and never changes its score.
No approved community evidence yet. Be the first verified user to contribute.
Respan is the new name for Keywords AI's LLM engineering platform, combining a model gateway, observability, evaluations, prompt management, and monitoring.
Respan lists a free plan, Team at $199 per month billed annually, metered log and score overages, and custom Enterprise pricing; model-provider usage is separate.
Yes. Its gateway supports a unified endpoint, provider fallbacks, retries, caching, load balancing, budgets, and rate limits.
No. Its automated and LLM-judge evaluations should be calibrated against expert labels before they block traffic or approve a release.
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