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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered externally. The description adds the either/or parameter rule with slug precedence and an alternate resource URI, but says nothing about auth requirements, rate limits, or error behavior. Useful but modest value on top of rich annotations.

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?

Front-loaded with the core action, then bracketed sections for usage and the resource alternative, with no filler sentences. The header-style formatting is a little heavy for such a short definition, but every line carries information.

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 read-only fetch with zero required params and no output schema, the description compensates by listing the returned fields, giving usage triggers, and offering an alternative access route. An agent has enough to select and invoke it correctly; only permission/error behavior is unaddressed.

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 coverage is 100%, giving a baseline of 3, and the description genuinely adds semantics beyond the schema: the two parameters are mutually exclusive alternatives and slug takes precedence. That precedence rule is real information the schema alone does not convey.

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 and resource (get full product details by id or slug) and enumerates the returned content (owner, description, links, media, category, tags, publish time). It clearly reads as the detail-fetch counterpart to list_products / search_products, but no sibling is named explicitly, so it falls short of a 5.

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 【何时用】 block gives concrete triggers: the user clicked a product, or a search/list result needs to be expanded. It also points to an alternative access path (resources/read with opcmenu://product/{slug}), which is real routing guidance. It stops short of stating when NOT to use it or naming the sibling list/search tools directly.

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