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

With readOnlyHint=true and openWorldHint=false already declared, the safety profile is covered, and the description usefully disambiguates the two sort modes as "launch date" vs "the day each went live." It says nothing about pagination (limit/cursor), default window behavior, or the shape/size of results, which matter for a 9-parameter listing call.

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 sentences, zero waste, with the positive case stated first and the exclusion second — exactly the order an agent needs to make a routing decision. Nothing is repeated from the schema or 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 is the only source of expectations about results, yet it says nothing about result volume or paging. For a 9-parameter tool with sub-50% schema coverage, an agent is left guessing how to page through a long "new since" window.

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 44%, so the description must pull weight — and it does for `sort`, translating released_at/first_seen_at into plain language that the bare enum would not convey. However, `limit`, `cursor`, `response_format`, and `store` have no descriptions anywhere and are left unexplained, so the coverage gap is only partially closed.

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 names the resource (apps in a store) and the scoping dimension (new since a given time, ordered by launch date or first-seen date), which is specific enough to separate it from a generic listing tool. It never uses an explicit verb like "list," but the intent is unmistakable. Sibling differentiation comes entirely from the next sentence rather than from the purpose statement itself.

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 gives a clear trigger (user asks which apps are new in a store since a time) plus an explicit exclusion with a named alternative: "Do not use for rank or toolset changes; use changes_list." What's missing is routing for the adjacent cases an agent will actually hit — e.g. finding a specific app by name, which presumably belongs to listings_search.

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