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

Annotations already declare read-only, open-world, and idempotent hints. The description adds valuable behavior: aggregates multiple catalog sources, returns up to limit InventoryItemCards with a detailed field list, and ranks verifiedBrand items based on KYB. Minor gaps remain, such as how query and brandSlug combine and the exact structure of nested objects like pricing.

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 dense but every sentence earns its place: main purpose, required inputs, optional filters, output format, and ranking guidance. It is front-loaded with the core function and logically structured, with no redundancy with annotations.

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?

There is no output schema, so the description's field list is the only return specification, and it includes optional markers and a ranking note. For a complex 10-parameter search tool, it covers essentials but leaves sub-structure of pricing/availability unexpanded.

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?

The schema has 0% description coverage across 10 parameters. The description compensates fully by explaining every parameter's meaning, including query as catalog match, brandSlug as scope, country as ISO-3166, currency examples, price bounds, verifiedBrand as attested only, inStockOnly, and source with its enum values. It also introduces the at-least-one-of constraint.

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 uses a specific verb ('Discover') with a clear resource ('droplinked inventory (SKU-level)') and scope ('across every connected catalog source'), naming the exact sources. This distinguishes it from sibling tools like search_products or get_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?

The description explicitly states the required input ('Provide at least one of query or brandSlug') and lists all optional filters with their allowed values. It also gives ranking guidance ('Prefer verifiedBrand=true'). However, it does not explicitly name sibling alternatives or state when not to use the tool, so it falls short of a 5.

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