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

With no annotations, the description carries the full disclosure burden, yet it says nothing about read-only nature, permissions, rate limits, or result shape. 'Comparison' hints at a multi-chain result but the agent cannot infer whether output covers all chains or is ranked.

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?

A single compact sentence with the core verb+resource front-loaded and the input guidance trailing. Efficient, though the example occupies space without adding much beyond what the schema already implies.

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 one-param read tool with no output schema and no annotations, the description covers the input side adequately but omits what the comparison returns (per-chain list? lowest price? sorted?). Given the dense sibling set of price-related tools, that gap matters.

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% (single param q = 商品關鍵字), so the baseline is 3. The description echoes that semantics and adds a concrete example ('舒酸定'), but contributes no format or matching-behavior detail beyond the schema.

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?

States a specific verb (compare) and resource (same product's price across chain stores), which is distinguishable from siblings like get_product_price and list_lowest_prices. However, it never names or contrasts those siblings, so differentiation is inferential rather than explicit.

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 parenthetical implies the input is a product keyword and gives a concrete example (舒酸定), which signals usage. But there is no statement of when to prefer this over get_product_price or list_lowest_prices, and no exclusions or prerequisites.

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