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

Annotations already declare read-only and idempotent, and the description adds genuinely non-derivable behavior: data scope (top 100 free and top-grossing in every Apple category, refreshed daily) and a hard free-tier truncation to 3 apps with paid access at $19/month. The truncation notice is the kind of thing that would otherwise cause an agent to silently under-report results.

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-loads what is searched, then filters, then return values, then the access constraint — a sensible order with no filler. The final pricing sentence is informal but conveys the paywall, so it earns its place. One dense run-on sentence does mild damage to scannability.

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?

With no output schema, the description carries the job of saying what comes back, and it does ('returns slugs for...'). Paging semantics are covered by the offset parameter description. It stops short of 5 because response shape (total match count vs. result items) is only implied via the schema rather than stated.

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 88%, so parameters are already well documented; the description only restates the filter categories. It does add the cross-tool prerequisite context by implying slugs come from list_directory_tags/list_directory_categories, but that is also already in the schema. 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?

States a specific verb and resource: searches a large App Store listings corpus with explicitly enumerated filters (text, genre slug, look tag, chart rank, video presence). It also names the downstream tools that consume the returned slugs, so an agent can place it in a workflow. It does not explicitly contrast itself with sibling list_directory_categories/list_directory_tags, which are prerequisites rather than alternatives.

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?

Clear about what inputs select what result sets and what the output feeds into (get_directory_app, get_app_videos, get_app_history, create_restyle). The free-tier cap of 3 apps is stated, which is actionable context. Explicit when-not-to-use guidance versus siblings is absent, so it stops 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.