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

Annotations already cover readOnlyHint, destructiveHint=false and closed-world scope, so the safety profile is set. The description adds valuable behavior beyond that: only active merchants are searched and only reviewed products are surfaced, plus cursor-based paging via next_cursor. It does not mention rate limits or result-ordering behavior, but the added filtering constraints are meaningful.

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?

Two tight sentences, front-loaded with scope and constraints, then return fields and pagination. No filler; every clause 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?

An output schema exists, so enumerating return fields is somewhat redundant but harmless. The description supplies the key filtering semantics (active merchants, reviewed products) and pagination model. With 6 params and just one required, a bit more on the optional filters would make it fully complete.

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 only 17% (merchant only), so the description must compensate. It clarifies 'slug' as the merchant identifier and gestures at cursor paging, but leaves query, limit, category, and max_price_usd completely undocumented in prose. It partially compensates but not fully.

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+resource+scope: 'Full-text search in one merchant storefront (slug)'. An agent can tell it apart from shop.catalog.get (single-product retrieval) and shop.merchant.* (management operations). However, it does not name those siblings explicitly, so the differentiation is inferred rather than stated.

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 implies usage by noting the search operates on one merchant and only returns reviewed products, but gives no explicit when-to-use/when-not or reference to the alternative shop.catalog.get for targeted lookups. Usage is implied, not guided.

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