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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read profile is covered. The description adds the supported-market list and the vertical-switching behavior of collection, but says nothing about rate limits, auth, or result paging beyond what the schema already documents.

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 purpose and markets, then the filter options and return fields. It is a single dense sentence, but each clause carries information; the trailing list of returned fields is the least essential part.

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 return values need not be explained, and the 100% schema coverage carries parameter detail. The description still conveys the market scope, vertical selection, and filter axes an agent needs, though it omits routing to sibling tools.

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 the schema fully documents all 15 parameters including filter pass-through semantics. The description only restates a subset (cuisine, dietary, top-rated, collection) without adding syntax or constraints beyond the schema, so baseline 3 is appropriate.

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 gives a specific verb and resource ('Deliveroo restaurant, grocery, or shopping-store search near a location') and even enumerates the returned fields (uname, name, image, rating, delivery time, distance). It clearly conveys a proximity search, but it never names or contrasts a sibling (e.g. deliveroo_restaurant, deliveroo_search_filters), so differentiation is left implicit.

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?

It provides real context for when a particular mode applies ('set collection to grocery or shopping', supported markets list) and notes optional filtering axes. However, it never states when to prefer this over siblings like deliveroo_search_filters or deliveroo_restaurant, and offers no explicit exclusions.

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