Hyperprobe (site) lets AI agents debug production issues without a redeploy. It's freemium: the free plan covers 1 service with unlimited probes/captures and 7-day history, while paid plans start at $99/service/month ($79/month billed annually, 3-service minimum), with custom Enterprise pricing above that.
| Product | Free tier | Starts at | Best for |
|---|---|---|---|
| AgentReplay | Yes (fully free/open-source) | Not stated (no paid tiers listed) | Local-only tracing and eval |
| debugai | Yes, 10 debugs/day | $12/mo | Solo devs and small teams |
| Retrace | Yes, 1,000 traces/mo | $29/mo | Replaying and forking agent runs |
| Trainly | Yes, 10K traces/mo | $49/mo | Quick trace audits before committing |
| Rookbot | Free trial | Not stated | Teams already on Dynatrace/Rookout |
| Goast.ai | Yes, 30-day trial | $499/mo | Automated fixes, not just debugging |
AgentReplay
AgentReplay (site) traces, evals, compares, and improves AI agents entirely on your own machine, with no cloud dependency. It suits teams that want privacy-first debugging or can't send agent data off-network. It's open-source and described as free, with no paid tiers or pricing mentioned anywhere. The honest limitation: there's no stated pricing for support, hosting, or enterprise features, so scaling plans or paid help aren't defined.
debugai
debugai (site) focuses on debugging tied to your actual codebase rather than generic error logs. It fits solo developers and small teams doing routine debugging. The free tier gives 10 debugs/day and 1 workspace scan/day; Pro is $12/month ($120/year, ~$10/month), with a $9/month lifetime founding rate available until December 7, 2026. Limitation: the free tier's daily debug cap is tight for anyone debugging multiple issues at once.
Retrace
Retrace (site) debugs AI agents by replaying and forking their runs, useful for teams reconstructing exactly what an agent did before a failure. It suits teams past the prototype stage that need repeatable trace inspection. Free plan includes 1,000 traces/month; paid tiers are Starter $29/month, Pro $99/month, Teams $399/month, and custom Enterprise. Limitation: high-traffic agents will likely outgrow the free 1,000-trace limit quickly.
Trainly
Trainly (site) offers a free 72-hour audit of an AI agent's production traces, aimed at teams wanting a fast diagnostic before committing to a tool. The free tier covers 10K traces/month, 500MB storage, and 7-day retention; Pro at $49/month raises this to 500K traces/month, 5GB storage, and 30-day retention. Enterprise is custom. Limitation: even on Pro, 30-day retention is short if you need longer historical comparisons.
Rookbot
Rookbot (site), from Rookout/Dynatrace, is billed as an AI virtual assistant for debugging. It's best suited to organizations already using Dynatrace's ecosystem. There's a free trial, but no specific pricing is disclosed for paid tiers. Limitation: without published pricing, it's hard to compare cost against the other options here or budget for adoption.
Goast.ai
Goast.ai (site) goes a step beyond debugging by automatically generating fixes for production crashes, including root cause analysis, resolution plans, and AI-generated pull requests. It suits larger engineering teams wanting automated remediation, not just visibility. The free 30-day trial includes 50 root cause analyses, 10 resolution plans, and 10 PRs; Pro is $499/month, with custom Enterprise pricing. Limitation: it's the most expensive option here, well above Hyperprobe's $99/month starting price.
How to choose
If budget is the priority, start with AgentReplay (free, local) or debugai ($12/month) for basic debugging needs. If you need to replay or fork agent runs specifically, Retrace is the closest match to that workflow. If you want automated fixes rather than manual debugging, Goast.ai is the only option here that does that, at a higher price. Confirm current pricing directly with each vendor before committing, since tiers change.
FAQ
Is there a fully free alternative to Hyperprobe? AgentReplay is free and open-source with no stated paid tiers.
What's the cheapest paid alternative? debugai's Pro plan at $12/month is the lowest stated paid price among the alternatives.
Which alternative does more than debugging? Goast.ai automatically generates fix plans and pull requests, not just diagnostics, at $499/month.