compare_urls

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

No annotations are provided, so the description must carry full behavioral disclosure. It does state plan limitations (Free up to 2 URLs, Pro up to 8) and that it 'Returns scores and check results for each URL,' which gives some insight into output. However, it does not describe auth requirements, error handling, or how 'agent readiness' is computed, leaving significant behavioral gaps.

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?

The description is concise, with three sentences that each serve a clear purpose: stating the core action, specifying plan limits, and indicating the return type. It is front-loaded with the most critical information and contains no filler or redundancy.

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 that there is no output schema, the description should clarify what 'scores and check results' include in more detail. It also does not explain the meaning of 'agent readiness' or define how the comparison is performed. While the single parameter and simple purpose reduce complexity, the description leaves gaps in understanding the output and tool nuances, making it adequate but not comprehensive.

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?

The input schema already fully describes the single parameter 'urls' with min/max items and plan-based limits (100% schema description coverage). The description repeats these limits without adding any new semantic meaning or examples. Therefore, it adds no extra value beyond the schema, warranting the baseline score of 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?

The description clearly states the tool's function: 'Compare websites side by side for agent readiness.' The verb 'compare' and the resource 'websites' are specific, and the phrase 'side by side' distinguishes it from single-URL audit tools like audit_url. It also implies a comparison use case that differs from bulk_audit and get_leaderboard.

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?

The description implicitly provides usage context by focusing on comparison of multiple URLs, which suggests it is appropriate when you need to evaluate several websites together. However, it does not explicitly mention when not to use it or name alternatives like 'use audit_url for a single URL.' Thus, it has clear context but lacks explicit exclusions.

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