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

With no annotations, the description carries the full behavioral burden. It says prices are compared across chain channels but does not disclose return format, data freshness, chain coverage, or any other behavioral trait. A basic read-only nature is implied but not detailed.

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?

It is a single, front-loaded sentence that efficiently covers the purpose, scope, input, and an example. No extraneous text, though the bracketed tag is slightly noisy.

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 no output schema and no annotations, the description should ideally explain what the comparison returns (e.g., a list of chain prices, a lowest-price summary, currency) and any data limitations. It does not, leaving the agent without critical context for interpreting results.

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%, so the schema already defines 'q' as '商品關鍵字'. The description adds only an example (舒酸定), which is a minor addition beyond the schema's own text.

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 names a specific verb+resource: comparing prices of the same product across chain channels, with a clear example keyword. It does not differentiate from sibling tools like shop__list_lowest_prices or shop__get_product_price, so it lacks full sibling distinction.

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 implies usage by stating the input is a product keyword and giving an example, but offers no explicit when-to-use versus alternatives or when-not guidance. The agent must infer that this is for cross-chain price comparison rather than single-store or lowest-price lookups.

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