URL Passport

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond annotations (readOnly, openWorld, idempotent, non-destructive), description reveals concrete behaviors: uses at most eight external HTTP requests, does not execute JavaScript, caches results with fresh=false, and rejects SSRF-sensitive destinations. No contradictions with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Four sentences, front-loaded with purpose, then key constraints and parameter guidance. No extraneous words; every sentence adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given two parameters and presence of an output schema, description covers all essential aspects: what tool does, what it finds, constraints (HTTP requests, no JS), caching policy, and security filter. Output schema already describes return values.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema covers both parameters with descriptions (100% coverage). Description adds practical usage advice: url must be absolute public HTTP(S) and fresh usage guidance. This extends schema details, justifying above baseline 3.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states 'Inspect a public HTTP or HTTPS URL and return a structured site passport' and enumerates included fields (pulse, domain, robots, sitemap, feeds, OpenAPI, metadata). This distinctively sets it apart from sibling tools that focus on individual aspects (e.g., url_pulse, site_robots).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides explicit usage context: url must be absolute public HTTP(S), cache guidance with fresh parameter, and limits (max 8 requests, no JavaScript). However, it lacks explicit when-not-to-use or direct comparisons to siblings, relying on sibling names for differentiation.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.