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

Beyond the annotations (readOnlyHint, idempotentHint, destructiveHint=false), the description discloses the multi-engine chain, the required x402 micropayment and cost, and the return shape of 'fresh source URLs, titles, and snippets.' This adds meaningful operational context an agent needs before invoking the tool.

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 well-structured and front-loaded: it states the core action, adds key constraints, then gives usage guidance and parameter details. Every sentence earns its place, with no filler or tautology.

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?

For a tool with only two parameters, an output schema, and clear annotations, the description provides all essential context: what it does, what it returns, when to use it, when not to use it, and the required micropayment. Nothing material is missing for an agent to select and invoke it correctly.

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 schema already documents both parameters with descriptions, defaults, and constraints, so coverage is 100%. The description repeats the same parameter details (e.g., query 3-300 chars, limit 1-10) without adding new semantic meaning or usage advice beyond what the input schema provides.

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 with a specific verb ('Execute live web searches') and resource ('web'), and details what it returns ('fresh source URLs, titles, and snippets'). This distinguishes it from siblings like read_web_page or fetch_stealth_web, which do different tasks. The explicit 'When NOT to use' also sharpens the boundary.

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 provides explicit 'When to use' and 'When NOT to use' guidance, including a concrete exclusion ('deep recursive crawling of entire sites'). However, it does not name an alternative tool for that excluded case or compare itself to siblings, so it stops short of full routing guidance.

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