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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), and the description adds real behavior on top: the data origin is an Appfigures sync, monetary values are in micros of `currency`, the revenue figure must not be combined with RevenueCat revenue, and the not-configured failure mode is disclosed. Those are exactly the details an agent cannot get from the annotations or schema.

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?

It is front-loaded with the payload contents, then adds the two constraints that prevent misuse, in three compact sentences with no filler. The dense enumeration is informative rather than redundant, since no output schema exists to convey the returned fields.

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 must convey the return surface — and it does, enumerating every metric family plus the `connected: false` case. With both parameters fully documented in the schema and annotations covering safety, nothing an agent needs to call this correctly is missing.

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%, with both `days` and `reviews` documented including defaults and bounds, so the schema carries the parameter burden. The description adds no parameter-level guidance (e.g., how lookback affects the ratings snapshot or review counts), 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 enumerates exactly what the tool returns (downloads, re-downloads, updates, uninstalls, store revenue, top countries, ratings snapshot, reviews, chart positions), which is a specific resource scope rather than a restatement of the name. It also separates itself from the RevenueCat-based analytics siblings by stating that store revenue is a distinct figure from RevenueCat revenue.

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?

The description gives clear operative context: these are store-reported (not RevenueCat) numbers, the two revenue figures must never be summed, and a `connected: false` signal indicates Appfigures is not configured. It stops short of an explicit 'use this instead of get_analytics when...' routing statement or any exclusion, so it stops at 4.

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