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

Beyond the annotations (readOnlyHint=false, idempotentHint=false, openWorldHint=true), it discloses billing mechanics, budget caps that can never be raised, the confirm_over_cap escape hatch, and a prompt-injection warning that results are third-party data, not instructions. That is unusually rich behavioral context.

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 paid/free routing and injection warning are front-loaded well, but the product entries are truncated mid-sentence ('section, port...', 'e.g.') and pricing is restated per product, making the block denser and less scannable than it needs to be.

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?

With no output schema, the description covers the essential return shape (dishes, drinks, prices, sections, scrape date) and the payment/precondition semantics. It is close to complete, though the truncated product entries leave minor gaps in what each product actually accepts and returns.

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 description coverage is 100% but the 'params' object is intentionally schema-opaque with additionalProperties=true; the description compensates by listing each product's required and optional params (restaurantId*, lat*, lon*, radiusKm, country*, area*) and defaults like 2 km.

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 states a specific resource (restaurants and their menus, with dishes and prices) and enumerates the three products with their ids and required params, so an agent can tell exactly what it returns. It partially differentiates from siblings by naming food_coverage and free_sample, though not the generic call_product.

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?

It clearly states the paid model ('each call is charged in USDC... only within the budget caps') and routes cost-averse callers to the free alternatives (food_coverage, free_sample) before paying. It does not, however, say when to prefer this tool over call_product.

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