UCPtools vs UCP Lighthouse: Which Validator Do You Need?
UCPtools goes deep on UCP with 4-level validation, generation, and simulation. UCP Lighthouse goes wide across UCP, Google Merchant, and OpenAI standards. Different tools for different needs.
The Short Answer
Choose UCPtools if you need deep UCP validation with actionable error codes, profile generation, agent simulation, and developer tools. Choose UCP Lighthouse if you need to validate across multiple standards (UCP + Google Merchant + OpenAI) or want an LLM friendliness score.
Feature Comparison
| Feature | UCPtools | UCP Lighthouse |
|---|---|---|
| Validation Approach | 4-level: structural, rules, network, SDK | Multi-standard: Google Merchant + UCP + OpenAI |
| Error Reporting | 20+ error codes with JSON paths and fix hints | Violation detection with community warnings |
| Agent Simulation | Full workflow: discovery, checkout, payment readiness | Basic agent simulation testing |
| LLM Friendliness Score | Not available | Agent/LLM friendliness scoring |
| OpenAI Readiness | Not available | OpenAI agent readiness check |
| Profile Generation | Full profiles + Ed25519/ES256 signing keys | Not available |
| Hosting Artifacts | Nginx, Apache, Vercel, Netlify, Cloudflare, AWS | Not available |
| Security Scanning | Endpoint security analysis + vulnerability detection | Not available |
| Feed Analysis | Product feed validation and optimization | Not available |
| PDF Reports | Downloadable validation reports | PDF report generation |
| REST API | Full API for CI/CD automation | Not available |
| CLI Tools | Command-line validator and generator | Not available |
| Platform Guides | Shopify, WooCommerce, Wix, Magento, BigCommerce, Squarespace | Not available |
| Standards Covered | UCP | UCP + Google Merchant Standard + OpenAI |
| Pricing | Free (paid tiers for monitoring) | Free |
Detailed Comparison
Validation Approach
The fundamental difference is scope vs depth. UCP Lighthouse validates payloads against three standards: Google Merchant Standard, UCP, and OpenAI agent requirements. UCPtools focuses exclusively on UCP but goes four levels deep — structural, rules, network, and SDK validation.
UCPtools
- Structural — JSON schema, required fields, version format
- Rules — Namespace/origin binding, extension chains, HTTPS enforcement
- Network — Remote schema fetching, endpoint reachability
- SDK — Official @ucp-js/sdk compliance
UCP Lighthouse
- Google Merchant Standard compliance
- UCP violation detection
- OpenAI agent readiness check
- Agent/LLM friendliness scoring
Error Reporting and Fix Guidance
UCPtools returns 20+ specific error codes, each with the exact JSON path and a hint explaining how to fix it. UCP Lighthouse provides violation detection with community warnings — useful for identifying issues, but with less granularity on the fix path.
Agent Simulation
Both tools offer some form of agent simulation. UCPtools tests the full workflow an AI agent would follow: discovery, capability inspection, checkout simulation, and payment readiness. UCP Lighthouse provides agent simulation testing as part of its multi-standard analysis.
UCPtools
- Discovery flow testing
- Capability inspection
- Checkout simulation
- Payment readiness verification
UCP Lighthouse
- Agent simulation testing
- Agent/LLM friendliness score
- OpenAI agent readiness check
Generation and Developer Tools
This is where the tools diverge most. UCPtools is a full implementation toolkit — it generates profiles, creates signing keys, produces hosting configurations, and provides API and CLI access for automation. UCP Lighthouse focuses on validation and analysis without generation capabilities.
UCPtools
- Full profile generation
- Ed25519/ES256 signing key generation
- Hosting artifacts for 6+ platforms
- REST API for CI/CD automation
- CLI tools for local workflows
- Platform guides for 6 e-commerce platforms
UCP Lighthouse
- PDF report generation
- URL fetching for remote validation
- JSON prettification tools
- No profile generation
- No API or CLI access
Security and Monitoring
UCPtools provides endpoint security scanning, product feed analysis, and benchmarking against the merchant directory. Paid tiers add automated weekly validation and email alerts. UCP Lighthouse does not currently offer security scanning or ongoing monitoring.
Pricing
Both tools are free for core functionality. UCP Lighthouse is entirely free. UCPtools is free for all validation, simulation, and generation features, with optional paid tiers for automated monitoring and managed hosting.
Which Tool Should You Use?
Choose UCP Lighthouse If:
- You need to validate across UCP, Google Merchant, and OpenAI standards
- You want an LLM friendliness score for your payloads
- You need OpenAI-specific agent readiness validation
- You want a broad compliance overview across standards
Choose UCPtools If:
- You need deep UCP validation with specific error codes and fix hints
- You're building a new UCP implementation from scratch
- You need signing keys, hosting configs, or platform guides
- You want to simulate full AI agent checkout workflows
- You need API or CLI access for automation
- You want security scanning and ongoing monitoring
Frequently Asked Questions
- What is UCP Lighthouse?
UCP Lighthouse (ucp.rest) is a JSON payload validator that checks compliance across multiple standards — Google Merchant Standard, Google UCP violations, and OpenAI agent readiness. It also provides an agent/LLM friendliness score and PDF report generation.
- How does UCP Lighthouse differ from UCPtools?
UCP Lighthouse validates payloads against multiple standards (UCP, Google Merchant, OpenAI) and provides an LLM friendliness score. UCPtools focuses specifically on UCP with deeper validation (4 levels, 20+ error codes), plus profile generation, agent simulation, security scanning, hosting artifacts, and developer tools (API, CLI). They take different approaches: breadth of standards vs depth of UCP tooling.
- Does UCPtools check OpenAI agent readiness?
UCPtools currently focuses on UCP protocol compliance, which covers Google AI Mode, Gemini, and any agent implementing the UCP standard. UCP Lighthouse additionally checks OpenAI-specific agent readiness. If you need OpenAI-specific validation alongside UCP, you may want to use both tools.
- Which tool should I use for Google Merchant Center compliance?
UCP Lighthouse validates Google Merchant Standard payloads in addition to UCP. UCPtools focuses on UCP profile validation. If you specifically need Google Merchant Center payload compliance checking, UCP Lighthouse covers that. For UCP profile validation with detailed error codes and fix hints, use UCPtools.
- Can I generate a UCP profile with UCP Lighthouse?
No. UCP Lighthouse validates existing payloads but does not generate profiles or signing keys. UCPtools generates complete UCP profiles, creates Ed25519 and ES256 signing key pairs, and produces platform-specific hosting configurations for Nginx, Apache, Vercel, Netlify, Cloudflare, and AWS.
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