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

Annotations cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description adds substantial context on top: results come from a stored daily collection, carry their collection date, and an uncollected term is queued for the next daily run rather than fetched live. It also explains what app_id does behaviorally by reporting that app's position.

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?

Four front-loaded sentences, each carrying distinct information: return contents, rank lookup, data freshness, and the queued-search behavior. There is no filler or repetition.

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 a four-parameter read tool with no output schema, the description covers return contents, ordering, freshness and the uncollected-term case well. The one gap is that it does not say what the response actually looks like when a search is queued (empty result set vs. a pending indicator), which an agent would need to interpret results correctly.

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 coverage is 100%, so all four parameters are already documented in the schema. The description adds only light reinforcement (results are per-country, app_id yields a position), which matches rather than extends the schema's own wording, so the baseline of 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?

The description gives a specific verb and resource: it returns App Store search results for a term in one country, including ratings, price, release date and Fledly's popularity/difficulty scores. It is implicitly distinguishable from siblings like get_top_charts or suggest_keywords, but it never names or contrasts with any sibling, leaving that differentiation to the reader.

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?

Usage is only implied: an agent can infer this is the tool for keyword-level App Store rankings and rank lookups via app_id. There is no explicit statement of when to prefer this over siblings such as get_top_charts or get_app, and no exclusions.

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