Catch AI regressions
before they hit
production.

Run your test cases against every prompt and model change. PromptLens compares the candidate to your baseline and shows exactly which cases broke — and why.

PromptLens

Support triage release check

9472−22 points

Baseline v16 vs candidate v17 · 50 cases · same model, same dataset

Regression detected

11 cases passed the baseline but fail the candidate.

Prompt changes · v16 → v17

[system]
You are a support triage assistant.
Categorize each ticket as billing,
technical, urgent, or general.
Escalate outages and revenue loss
as "urgent", even when technical.
Reply with the single most
specific category.

model gpt-5.4 · temperature 0.2 · unchanged

Cases that flipped · pass → fail

"The checkout page is down and we are losing orders every minute."

urgenttechnical

JudgeMissed the urgency signal on a production outage with revenue loss.

"I was charged twice and my card closes tomorrow."

urgentbilling

JudgeDouble charge with deadline pressure should escalate as urgent.

"Can you send me the invoice for last month?"

billingThe message is about billing.

JudgeReturned prose instead of the required single lowercase category.

Recommendation: Block the release. Restore the escalation rule in v17, then rerun the suite.

Start with a demo preset, then run release checks across the model providers your organization approves.

OpenAI
Anthropic
Google
Meta
DeepSeek
Mistral
Decisions

One regression report, one release decision.

Compare a candidate AI change against a known-good baseline. PromptLens shows what got worse, what likely changed, and whether to ship, block, rollback, or rerun.

Decision ledger

Support triage regression check

Report ready50 cases scored
01

Catch a quality drop

Check
Did the candidate get worse than the baseline?
Evidence
Baseline score, candidate score, failed cases, judge reasons
Action
Block the release before the regression reaches users.
02

See what changed

Check
What changed before quality dropped?
Evidence
Prompt diff, model and settings changes, judge reasons
Action
Start from the cases that flipped from pass to fail.
03

Share the release decision

Check
Should the team ship, rollback, or rerun?
Evidence
Recommendation, examples, score deltas, report link
Action
Send one report with the evidence attached.

Next step: ship, block, rollback, or rerun.

The shared report keeps failed examples, score shifts, and the recommendation attached to the decision.

Evidence surface

Make every outcome inspectable.

A regression report only earns trust when raw output, score shifts, failure reasons, likely causes, and the recommendation stay attached to the same run.

What the report carries

Baseline versus candidate review

Every output stays beside the prompt version, dataset row, scorer, score, and run metadata.

Regression detection

PromptLens shows which AI changes fall below the release bar before they reach production.

Pass-to-fail flips

See exactly which cases passed the baseline but fail the candidate, with the judge's reason for each, next to the prompt diff.

Decision-ready links

Send one report URL to a teammate, stakeholder, or PR with the conclusion attached.

Organization model access

Team evaluations use approved provider access instead of personal scripts or hidden shared keys.

Pricing

Start free. Upgrade when your suites grow.

Every plan includes evaluations with LLM judge scoring, baseline comparisons, and unlimited shared regression reports. Live runs use encrypted organization provider keys so model choice and spend stay under your control.

Free

$0/month

Run real regression checks today. No card, no setup, no provider keys required.

Pro

Recommended
$99/month

Bigger test suites, more projects, and higher daily volume for weekly AI releases.

Teams

Custom

Higher volume, organization provider keys, and a security review for your team.

Projects

Free3
Pro10
TeamsCustom

Prompts

Free10
ProUnlimited
TeamsUnlimited

Evaluation runs

Free50 per day
Pro100 per day
TeamsCustom

Test cases per dataset

FreeUp to 50
ProUp to 200, plus comprehensive datasets
TeamsCustom

Playground calls

Free50 per hour
Pro500 per hour
TeamsCustom

LLM judge scoring

FreeIncluded
ProIncluded
TeamsIncluded

Shared report links

FreeUnlimited
ProUnlimited
TeamsUnlimited

Model access

FreeOrganization provider keys
ProOrganization provider keys
TeamsProvider policy controls

Support

FreeEmail
ProPriority email
TeamsDedicated

Billing note

Live evaluations use your organization's provider keys. PromptLens records provider-reported or estimated usage so every comparison shows quality, latency, and model cost.

No card required to start
FAQ

Frequently asked questions

Common questions about PromptLens and how it compares to the tools you're already using.

Catch regressions before production.

Compare a candidate against a known-good baseline and share the evidence behind the release decision.