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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so safety is covered; the description goes further with non-obvious behavior: product names must be Italian, flyer prices are indicative and the in-store price prevails, and results render as cards in MCP Apps hosts. These are real operational caveats not derivable from structured fields.

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 when-to-use condition and otherwise dense, but the sentence enumerating return fields (price, previous price, pack size, price per kg, department, chain, expiry, link) duplicates the existing output schema and could be trimmed.

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 an 8-parameter zero-required search tool with annotations and an output schema, the description supplies everything an agent needs: trigger, geographic limitation, language constraint on query, data-quality caveat, and host-dependent rendering. No material gap remains.

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 every parameter is already documented (city radius, sort enum meanings, pagination, chain list, price cap). The description restates those filters and repeats the Italian-query requirement rather than adding format or syntax detail beyond the schema, so the baseline 3 applies.

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 (search offers in flyers) with explicit scope: currently valid Italian supermarket/discount/electronics flyers, with filters and sorting. The 'covers Italy only, not online-shop prices' clause makes it easy to distinguish from siblings like search and list_current_flyers.

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?

Opens with an explicit trigger condition ('Use this when the user wants to know where a product is on offer ... and you need filters or sorting'), enumerates the concrete filter/sort scenarios, and states two exclusions (other countries, online-shop prices). Nothing about when to prefer or avoid it is left to inference.

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