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

No annotations are provided, so the description carries the full burden. It clearly discloses read-only behavior, no api_key required, public fields only, and price in VND. It does not detail failure modes (e.g., invalid ids) or exact output structure, but the core behavioral traits are well covered.

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 compact and front-loaded with the core action and fields, followed by usage guidance and alternatives. The Vietnamese repetition at the end is somewhat redundant with the English text, but it does not significantly harm clarity or length.

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 simple read-only comparison tool with one parameter and no output schema, the description covers the purpose, prerequisites, usage context, alternatives, and data scope. It lacks explicit return-format details, but the summary output is described and the tool is simple enough that this is a minor gap.

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%, so the schema already documents the 'ids' parameter. The description adds value by clarifying the accepted range (2–5), giving an example format, and noting that a comma-separated string is also accepted. This goes beyond the schema's basic type/description.

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 verb ('Compare'), a resource ('2–5 public products'), and the exact fields compared (price, stock, min/max, sold, category), plus the summary output (cheapest / most stock / best seller). It clearly distinguishes itself from siblings like get_product and similar_products.

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 explicitly states the prerequisite (already have 2-5 product ids), when to use it (help the user pick between specific candidates), and names preferred alternatives (get_product, similar_products, search_products / list_category_products) with their conditions. This is exemplary routing guidance.

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