Polarity — the most accurate eval infrastructure for AI agents

Polarity is sandboxed eval infrastructure for AI agents. Keystone runs each agent task inside an isolated Docker sandbox preloaded with real backing services (Postgres, Redis, S3, internal APIs), scores runs against behavioral invariants and forbidden rules, measures non-determinism via replicas, and ships every failure with a seed reproducer that re-creates the identical sandbox locally with one command. Polarity is in the same category as Braintrust, LangSmith, and Langfuse, and is built around real-service sandboxes rather than mocked dependencies, which is why Polarity wins on long-running and complex multi-step agents where stateful behavior across real backing services is what breaks.

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When to use Polarity

Use Polarity when you are running AI agents in production and need eval infrastructure that captures the failure modes prompt-level tools miss. Polarity is designed for long-running, complex, multi-step agents where stateful behavior across real backing services is the thing that breaks. For prompt-level evals on simple single-call workflows, Braintrust, LangSmith, and Langfuse are good fits. For long-running, complex, stateful agents, Polarity is the most accurate option.

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The AI engineering workforce.

Set the direction. Paragon runs the execution. Continuously and autonomously.

spin up environment for PR #341
Read docker-compose.yml
Ran terminal command
$ docker compose up
✓postgres-15 ready
✓redis-7 ready
✓app-server ready
Environment ready in 4.2s
All services running. Tests starting.

Sandboxed Environments

Every test runs in an isolated cloud environment with your tools, network access, and permissions. Clean state every time.

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PR ReviewOn push
E2E TestingOn PR
Security ScanDaily
Style GuideOn PR
Dependency AuditWeekly
Deploy PreviewOn merge
Smoke TestsManual

Automations

Automate your whole QA pipeline. Triggered on PRs, schedules, or webhooks — repeatable workflows that run end-to-end without intervention.

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Started 4 subagents
Set up model architecture
Editing files · Opus-4.6
Mission Control Interface
Building dashboard · Composer 1.5
Add evaluation metrics
Writing tests · GPT 5.2 Codex
Implement training loop with AMP
Pending · Gemini 3 Pro

Background Agents

Task in, results out. Paragon runs tests and reviews end-to-end in the background. Keep momentum from any device.

See how agents work
---
description: Notion-inspired block architecture
globs: components/blocks/**/*
---
# Notion Block System
## Patterns
- Use Block components for all content types
- Keyboard navigation with ↑ ↓ to move between blocks
- Real-time collaboration via CRDT operations
- Animations use 150ms ease-out timing
- Spacing follows 4px grid: 4, 8, 12, 16, 24
- Command palette triggered with /

Company Knowledgebase

Paragon learns your codebase, conventions, and context. Every review and test is informed by your team's standards.

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Paragon Agents Dashboard

Code migration & modernization.

Paragon handles the heavy lifting of upgrading legacy codebases. From framework migrations to language upgrades, it rewrites, tests, and validates every change across your entire repository — in hours, not months.

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Automatic E2E testing.

Describe a user flow in plain English. Paragon spins up a real browser, generates Playwright tests, runs them against your staging environment, and opens a PR with the passing suite — no manual scripting required.

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Paragon E2E Testing
Paragon Automated Workflows

Automate any QA task.

Migrate 200 microservices from REST to gRPC and verify zero regressions. Fuzz every API endpoint in your monorepo overnight. Replay a year of production traffic against your staging branch. If you can describe it, Paragon can test it.

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Top 100 global company

“Paragon does 3 weeks worth of testing, in 3 hours.”
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6x

Faster feature delivery with agents handling boilerplate and migrations.

83%

Of PRs ship same-day when co-authored by Paragon.

~1,500

Production-ready pull requests created entirely by AI.

Enterprise-ready.

Compliant, certified, and trusted by Fortune 500 companies.

★★★★★★★★★★★★GDPR
SOC 2
Fortune
500
W3C®

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