Teams operating multiple model providers and Developers debugging production AI agents.
Who should avoid it?
Workloads that cannot send traces through a third party, Teams needing an evaluator to act as ground truth
What problem does it solve?
Respan, formerly Keywords AI, combines a multi-model gateway with tracing, cost monitoring, prompt management, datasets, evaluations, alerts, and production controls.
Would I recommend it?
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.
Respan, formerly Keywords AI, combines a multi-model gateway with tracing, cost monitoring, prompt management, datasets, evaluations, alerts, and production controls.
Direct verdict
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.
What to verify
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
See whether Respan belongs in your stack
Gateway, traces, evaluations, and prompts in one platform
Teams operating multiple model providers, Developers debugging production AI agents, Organizations unifying gateway, prompts, evals, and spend.
Who should avoid it?
Workloads that cannot send traces through a third party, Teams needing an evaluator to act as ground truth
What problem does it solve?
Respan, formerly Keywords AI, combines a multi-model gateway with tracing, cost monitoring, prompt management, datasets, evaluations, alerts, and production controls.
Would I recommend it?
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.
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 For
Teams operating multiple model providers
Developers debugging production AI agents
Organizations unifying gateway, prompts, evals, and spend
Not Recommended For
Workloads that cannot send traces through a third party
Teams needing an evaluator to act as ground truth
Simple low-volume prototypes with no operations burden
Recommended Because…
Gateway, traces, evaluations, and prompts in one platform
Scores use a 0-10 editorial scale. The source data is maintained as 5-point review dimensions, then normalized for reader-friendly comparison.
Reusable trial worksheet
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DiscoverAI evaluation worksheet
Respan Review 2026: LLM Gateway, Observability, Evals, and Pricing
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.
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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Product interface evidence
Visual evidence statusWhat we verified without a screenshot
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.
Pricing
Freemium
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 1,000 scores; additional Team seats are $15 per member. Enterprise and model-provider charges are separate or custom. Reviewed September 9, 2026.
Free plan: Yes. The Free plan includes the full platform within published log, score, prompt, evaluator, dataset, retention, and throughput limits.
Editorial freshness
Checked this month
Pricing and material product claims were checked September 9, 2026.
Pros & Cons
Pros
Gateway, traces, evaluations, and prompts in one platform
Useful free limits for a production-shaped pilot
Published overage and retention boundaries
Cons
Creates a central traffic and telemetry dependency
Team price requires annual billing
Judges and fallbacks need independent validation
Best For
Teams operating multiple model providersDevelopers debugging production AI agentsOrganizations unifying gateway, prompts, evals, and spend
Community evidence
How verified users put Respan to work
Structured, editor-moderated experience—not star ratings. This complements our independent review and never changes its score.
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Key Features
Multi-model gateway
Agent tracing
Evaluations
Prompt management
Cost monitoring
Operational alerts
Integrations
OpenAI SDK
Vercel AI SDK
LangChain
LlamaIndex
Mastra
OpenTelemetry
FAQs
What is Respan?
Respan is the new name for Keywords AI's LLM engineering platform, combining a model gateway, observability, evaluations, prompt management, and monitoring.
How much does Respan cost?
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.
Can Respan route between AI models?
Yes. Its gateway supports a unified endpoint, provider fallbacks, retries, caching, load balancing, budgets, and rate limits.
Does Respan replace human evaluation?
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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