get_today

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety and side-effect profile is fully covered. The description adds useful semantic context about what is aggregated and that tz redefines 'today', but says nothing about pagination, freshness/latency of the figures, or auth requirements. With annotations carrying the safety burden, a 3 is appropriate.

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?

The answer is front-loaded with the core scope, and the long enumeration of returned fields earns its place because there is no output schema. The first sentence is dense and run-on, which costs some readability, but nothing is redundant.

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's comprehensive enumeration of returned data is exactly what the agent needs to know what to expect. Read-only behavior is covered by annotations. The main residual gaps are freshness of the figures and any usage-vs-alternative routing, but for a read-only digest tool this is largely complete.

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 the schema base is documented (tz, day, appId), giving a baseline of 3. The description adds meaning beyond the schema for tz by explaining its effect — it makes 'today' the user's own calendar day rather than UTC — which is real semantic value. It does not discuss the day parameter, but the schema covers it adequately.

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 states a specific scope ("One app's day in one answer — the Today screen") and enumerates the concrete resources it aggregates: purchases, trials, renewals, reviews, rank/category moves, events, and prior-day store/proceeds/ads figures. That is far more specific than a restated name. It stops short of explicitly distinguishing itself from list-oriented siblings such as get_portfolio_overview or get_history, so it is clear but not maximally differentiated.

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 implied by the 'daily digest' framing — an agent can infer this is the broad single-app summary versus the narrow keyword/review/revenue tools. However, there is no explicit when-to-use statement, no when-not-to-use, and no named alternative. That is minimum-viable guidance.

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