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

Adds substantial behavior beyond the annotations: latency ('takes up to a minute'), a quota cost ('uses one of the workspace's daily report runs'), additive semantics ('adds a report without changing older ones'), and the return payload. This is exactly the context a describing layer should supply on top of readOnly/destructive flags.

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?

Three tight sentences with zero filler: purpose first, then cost/latency, then result. Every clause (data sources, duration, quota, additive behavior, return fields) earns its place.

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 no-arg, non-idempotent write tool with an output schema, the description covers purpose, side effects, resource consumption, latency, and safety (older reports untouched). Nothing material is missing, and return values are already defined by the output schema.

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?

Zero parameters, so there is nothing for the description to disambiguate; the baseline for a no-arg tool applies. The description correctly avoids inventing parameters.

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 ('Creates a new report for the connected workspace') plus its data sources (Stripe/RevenueCat, posts, marked events). It implicitly separates itself from reading existing reports ('adds a report without changing older ones') but never names get_latest_report as the read counterpart, so sibling differentiation is left to inference.

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: 'from its latest data' and the website-button analogy suggest you call this when you want a fresh snapshot rather than an existing report. It never states when to prefer get_latest_report, nor any when-not conditions, so the agent must infer the routing decision.

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