Respan
Route, trace, and evaluate every LLM call from a single LLM gateway
If you're running more than one model in production and still stitching routing, traces, and evals from separate vendors, Respan collapses that stack into one SDK and one bill. The Team plan's $199/mo entry price and a 100k-log Free ceiling mean small projects should test with realistic traffic before committing. For agent teams that want evals running on live spans rather than in a notebook, the consolidation is worth the premium.
Verified 1d ago · liveness 84/100 · cite: rightaichoice.com/tools/respan
- Engineering teams running multi-provider LLM apps that need routing, tracing, and evals on one endpoint
- Platform teams building internal AI infrastructure with per-customer budgets and rate limits
- Agent builders who need trace-level debugging across tool calls, retrievals, and multi-turn threads
- Teams that want to evaluate live production traffic instead of only offline test sets
- Hobbyists on tight budgets — Free caps at 100k logs and 1k scores, then jumps to $199/mo
- Single-model teams with no failover or provider-switching needs; the gateway adds cost without payoff
- Buyers who want a standalone monitoring tool without adopting a routing layer
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Skip Respan if you're a hobbyist or small team needing a generous free tier—the 100k log cap fills fast—or if you use only one or two models and don't need a unified gateway.
Additional logs cost $8 per 100k logs over the free tier's 100k limit, which can add up at high volume.
Respan's pricing fits startups and growing teams that need production-grade routing, tracing, and evals but don't want to stitch together multiple tools. At $199/mo, it's pricier than standalone monitoring tools like LangSmith's free tier, but cheaper than assembling equivalent gateway + observability + eval solutions. For teams with high volume, the $8/100k log overage is competitive, and the Enterprise plan offers volume discounts.
In short
Respan — Route, trace, and evaluate every LLM call from a single LLM gateway. Best for Engineering teams running multi-provider LLM apps that need routing, tracing, and evals on one endpoint, Platform teams building internal AI infrastructure with per-customer budgets and rate limits, Agent builders who need trace-level debugging across tool calls, retrievals, and multi-turn threads. Free to start; paid plans from $199/mo.
What's new in Respan
Checked 17 days agoAcross the latest 2 updates: 2 feature updates.
New response formats, online evaluation alerts, improved experiments
Added saved response formats, online eval alerts, stabilized trace loading, reasoning+tool calls in experiment inference, and updated model catalog.
Native OpenRouter endpoint, agent full-text search
Added a native OpenRouter chat completions endpoint and full-text search for the Respan Agent.
What people actually say about Respan — is it worth it?
We ran a structured research pass across product reviews, community discussions, and post-purchase forum threads to surface the patterns vendors won't publish themselves. Below: the recurring strengths, the hidden costs people mention most, and the cohort that consistently regrets adopting this tool.
48 mentions across 4 sources (Hacker News, YouTube, Bluesky, Lemmy) · researched Jul 23, 2026.
Average across the 4 sources that answered — each source counts once, not each post.
- +Unified gateway for 500+ LLM models from one API.
- +Automatic fallback, retry, and load balancing across providers.
- +Built-in evaluation with LLM judges, code checks, and human review.
- +Detailed trace trees with latency per span for debugging.
- +Custom dashboard charts with SQL, cost-by-key, and metrics.
- −Only one Hacker News user called it 'too much of everything'.
- −Very few real user reviews — hard to validate reliability.
- −Learning curve may be steep for smaller teams or solo devs.
- −No community case studies or third-party benchmarks yet.
- −Potential confusion with other products sharing the 'Respan' name.
- • Overage charges for exceeding free-tier request limits.
- • Cost for additional team seats beyond basic plan.
Viability Score
How well maintained and how widely used is Respan? Built from what the vendor actually publishes (docs, changelog, tutorials, integrations, pricing), whether the site is live, and how much real users discuss it. How we calculate this
Last calculated: September 2026
How we score →Key Features
- Unified gateway endpoint reaching 1,000+ LLM models
- Native OpenRouter chat completions endpoint
- Automatic fallbacks and auto retries when a model errors or rate-limits
- Response caching to cut cost and latency on repeat requests
- Budgets and rate limits per key, per customer, or org-wide
- Load balancing across provider keys with BYOK key vault
- Trace tree view capturing LLM calls, tool runs, retrievals, and agent turns
- Agent full-text search across traces
- Custom observability dashboards for requests, errors, cost, latency, and tokens
- Alerts to Slack, email, webhook, or Microsoft Teams on threshold breach
- LLM-as-judge evaluators with written rationales
- Deterministic code checks and human annotation queues
- Online evaluations sampling production traffic with eval alerts
- Datasets built from filtered trace sampling or CSV upload
- Red Team online security assessments with reports
About Respan
Respan is an LLM engineering platform that puts three usually-separate jobs on one endpoint: an AI gateway, tracing and observability, and evaluation. Instead of wiring Portkey for routing, LangSmith for traces, and a spreadsheet for eval scores, engineering teams point their existing SDK at Respan and get all three back on the same request. It suits teams already running agents, chatbots, or RAG pipelines in production — not someone still deciding whether to use an LLM at all. The gateway is the hook. Send every request to one endpoint, reach 1,000+ models across OpenAI, Anthropic, Google, Bedrock, and more, and switch providers by changing a single word. Automatic fallbacks take over the moment a model errors or rate-limits, response caching serves repeat calls instantly, and budgets plus rate limits apply per key, per customer, or org-wide so spend can't run away. A native OpenRouter chat completions endpoint, added in August 2026, means you can route through OpenRouter without leaving the platform. Observability turns every LLM call, tool run, retrieval, and agent turn into a span in one trace with input, output, latency, and cost attached. A single dashboard tracks requests, errors, cost, latency, and tokens sliced by model, key, or user, and fires alerts to Slack, email, Teams, or a webhook the instant a threshold breaks. Agent full-text search and stabilized trace loading landed in the August 2026 release. Evaluation composes LLM judges, deterministic code checks, and human review into one evaluator that scores sampled production traffic or uploaded CSV case sets; online eval alerts and saved response formats are the newest additions. Datasets pull straight from traces by filter and sampling rate. Compare version score distributions before you ship, and use Red Team assessments plus SOC II, HIPAA, and GDPR coverage for security review. It's a confident alternative to point tools like LangSmith, and a migration path off Portkey.
Behind the Verdict
The pitch that matters here is the loop, not any single feature. Route a call through the gateway, watch it land as a span, sample that span into an evaluator, then compare the new prompt version's score distribution against the old one. Very few vendors close that circle end to end, and that's what Respan is actually selling. Pick it when you're past prototype. Once you have paying users on an AI feature, the fallback behavior and the per-customer budget caps stop being nice-to-haves — a single provider outage becomes a support queue, and a runaway key becomes an invoice. Teams standardizing internal AI infrastructure get the most out of the gateway plus shared dashboards. Pass if you're single-provider and single-model. The gateway's core value is failover and switching cost, and if you'll never switch, you're paying for insurance you don't need. Hobbyists should also look elsewhere: 100k logs and 1k scores look generous until real traffic hits them, and the jump to $199/mo is abrupt. Against LangSmith, the difference is consolidation — Respan owns the routing layer, so traces start at the gateway rather than wherever your app instrumented itself. Against migrating Portkey users, the draw is production evals and datasets that Portkey never bundled. Neither comparison favors Respan on price at the low end. Watch the metering. Additional logs run $8 per 100k and additional scores $1 per 1k beyond your tier, so a high-volume team on Team can outgrow the $199 headline quickly. Default retention is 30 days on Team versus 7 on Free — check that against your compliance window before you assume you have history when you need it. Self-hosting and SAML SSO are Enterprise-only, and HIPAA compliance is an add-on at $249/mo even above Team. Regulated teams should price the
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Real-world workflow fit
Concrete scenarios for the personas Respan actually fits — and what changes day-one when you adopt it.
You're building an internal AI gateway for multiple product teams. You sign up, get an API key, change your SDK base URL to Respan's endpoint, and start routing calls to GPT-5.5, Claude Opus 4.7, and Gemini 2.5 Pro. You set up fallbacks so if one provider rate-limits, traffic goes to the next. You create budgets per team and get Slack alerts when spend nears limits.
Outcome: Within an hour, you have a single endpoint for all teams, automatic failover, spend controls, and full logging of every call as a span.
You need to evaluate a new prompt version against production traffic. You sample 2% of live requests, build a dataset, set up an LLM judge with written rationales, and run an experiment comparing your current prompt vs a new one. You see score distributions side by side and ship the winner.
Outcome: You catch a regression before it hits users and deploy the higher-scoring prompt, with evidence-based confidence.
You set up tracing for your agent, create a dashboard with error rate, cost, and latency, and configure alerts to Slack and Microsoft Teams. When error rate spikes, you dig into the error tracking view, see an impact summary and timeline, and identify the culprit span.
Outcome: You resolve incidents faster with root-cause context, and you're alerted within seconds of a metric breach.
Use Cases
- Debugging multi-agent workflows in production to identify where a sub-agent failed.
- Building evaluation pipelines that combine LLM judges and human reviewers to score agent responses.
- A/B testing prompt variants across models and deploying the best-performing prompt to production.
- Monitoring cost and latency across different LLM providers to optimize spend.
- Creating regression test suites from real production traces to prevent regressions after updates.
- Setting cost and request limits per API key to control spending and prevent abuse.
- Migrating from Portkey after its acquisition by Palo Alto Networks.
- Running Red Team security audits on your agent to detect prompt injection and data leakage.
Models Under the Hood
as of 2026-08-30
Limitations
- Free tier is capped at 100k logs and 1k scores.
- Team plan costs $199/month (billed yearly).
- Enterprise plan offers custom packages and volume discounts.
- Additional logs cost $8 per 100k.
- Additional scores cost $1 per 1k.
- Additional seats on Team plan cost $15 per member per month.
- Self-hosted deployment requires Enterprise plan.
- No fully on-prem option below Enterprise.
as of 2026-08-29
Verification history
We have re-verified Respan 17 times since . Each pass re-reads the vendor's own pages and re-checks every listed field against that evidence; passes where nothing had changed are marked as such.
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
- — re-verified summary, description, our verdict, our analysis, pricing model, pricing tiers, features, integrations, who it suits, who should skip it
Showing the 6 most recent of 17 verification passes.
Free to cite with attribution — this page re-verifies continuously.
12-month cost
Project the real annual outlay, including the implied monthly cost when only an annual tier is published.
Vendor list price only. Add-on usage, seat overages, and contract minimums are surfaced under Hidden costs & gotchas.
Plans compared
For each published Respan tier: who it actually fits, and what it adds vs. the previous tier. Cross-reference the cost calculator above for projected annual outlay.
Free
$0/mo
Ideal for
Developers and small teams exploring Respan with modest traffic—up to 100k logs and 1k scores, perfect for initial prototyping and testing the platform.
What this tier adds
Full platform access with 100k logs, 1k scores, 5 datasets, 2 evaluators, 5 prompts, and 7-day retention—enough to evaluate fit before committing.
Team
$199/mo billed yearly
Ideal for
Startups and growing teams that need unlimited datasets, evaluators, and prompts, plus higher throughput (8,400 req/min) and 30-day retention.
What this tier adds
Adds unlimited datasets, evaluators, and prompts, 10k scores, 30-day retention, private Slack channel, and SOC 2 report for $199/mo billed yearly.
Enterprise
Custom
Ideal for
Large organizations needing custom SLAs, volume discounts, dedicated support, HIPAA BAA, self-hosted options, and SAML SSO.
What this tier adds
Adds custom packages, volume discount, custom SLAs, dedicated support engineer, HIPAA BAA, self-hosted options, and SAML SSO.
Where the pricing makes sense
The company stage and team size where Respan's pricing actually pencils out — and where peers do it cheaper.
Respan's pricing fits startups and growing teams that need production-grade routing, tracing, and evals but don't want to stitch together multiple tools. At $199/mo, it's pricier than standalone monitoring tools like LangSmith's free tier, but cheaper than assembling equivalent gateway + observability + eval solutions. For teams with high volume, the $8/100k log overage is competitive, and the Enterprise plan offers volume discounts.
Setup time & first value
How long it actually takes to get something useful out of Respan — broken out by persona, not the marketing-page minute.
For the gateway: minutes. Change your base URL, add fallbacks, and you're routing. For tracing: ~30 minutes to install the SDK and start seeing spans. For evals: under an hour to build a dataset from production logs and run your first experiment. Red Team campaigns take a bit longer to configure but produce reports automatically.
Switching to or from Respan
How to bring data in from common predecessors and how to get it back out — written for the switcher, not the buyer.
- →From Portkey: change your base URL to Respan's endpoint and import your existing API keys and models; your code remains mostly unchanged.
- →From LangSmith: you'll need to replace tracing calls with Respan's SDK decorators, but your prompt and eval logic can be recreated in Respan's interface.
- ↗To LangSmith: you can export traces and datasets via batch export (JSONL, CSV) and import them into LangSmith's format.
- ↗To an in-house solution: use the API to pull your logs and traces, and the OpenTelemetry support to retain instrumentation.
Integrations
Resources & Guides
- Documentationrespan.ai
What is Respan?
Respan is a full-stack LLM engineering platform for developers and PMs.
- Resourcerespan.ai
Overview
Integrate Respan with your LLM stack
- Resourcerespan.ai
Core concepts
Spans, traces, threads, and how Respan organizes your LLM data.
- Resourcerespan.ai
Changelog
Helpful link from respan.ai
Tutorials & Learning
YouTube returned 6 videos for “Respan”, and we withheld 6: 6 could not be judged, because “Respan” is a single word that other videos use for other things. We are showing none, because we could not prove any of them are about Respan.
Official links
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