L0
logocat.vercel.app.
L0 — not silicon friendly yet
Logocat is a free web service that retrieves and displays the logo of any website by its URL. It provides an easy-to-use interface for fetching favicons and brand logos from across the web, making it useful for developers and AI agents that need to display or reference website branding assets programmatically.
LEVEL 1 /
BASIC ACCESSIBILITY
— 3/6
Uses semantic HTML elements (header, nav, main, article, section, footer) instead of just divs
FAIL
Has proper meta tags (title, description, og:tags, twitter:card)
FAIL
Includes Schema.org JSON-LD structured data
FAIL
Does not block automated access with CAPTCHAs on public content
PASS
Content is server-side rendered (visible in HTML source, not just JS-rendered)
PASS
Uses clean, readable URLs (no excessive query params or hash fragments)
PASS
LEVEL 2 /
DISCOVERABILITY
— 1/6
Has a robots.txt that allows legitimate bot access
FAIL
Provides an XML sitemap
FAIL
Has a /llms.txt file describing the site for LLMs
FAIL
Publishes an OpenAPI/Swagger specification for its API
FAIL
Has comprehensive, machine-readable documentation
FAIL
Primary content is text-based (not locked in images/videos/PDFs)
PASS
LEVEL 3 /
STRUCTURED INTERACTION
— 0/6
Provides a structured REST or GraphQL API
FAIL
API returns JSON responses with consistent schema
FAIL
API supports search and filtering parameters
FAIL
Has an A2A agent card at /.well-known/agent.json
FAIL
Rate limits are documented and return proper 429 responses with Retry-After
FAIL
API returns structured error responses with error codes and messages
FAIL
LEVEL 4 /
AGENT INTEGRATION
— 0/6
Provides an MCP (Model Context Protocol) server
FAIL
Supports WebMCP for browser-based agent interaction
FAIL
API supports write operations (POST/PUT/PATCH/DELETE), not just reads
FAIL
Supports agent-friendly authentication (API keys, OAuth client credentials)
FAIL
Supports webhooks for event notifications
FAIL
Write operations support idempotency keys
FAIL
LEVEL 5 /
AUTONOMOUS OPERATION
— 0/6
Supports event streaming (SSE, WebSockets) for real-time updates
FAIL
Supports agent-to-agent capability negotiation
FAIL
Has a subscription/management API for agents
FAIL
Supports multi-step workflow orchestration
FAIL
Can proactively notify agents of relevant changes
FAIL
Supports cross-service handoff between agents
FAIL