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

Annotations already cover the read-only, idempotent, and non-destructive safety profile. The description adds behavioral context beyond that: the default last-30-day range, conversion into one reporting currency, and the multi-store plan requirement. No contradiction with the annotations.

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 short sentences that front-load the core purpose and scope, then mention the optional breakdown and the prerequisite. There is no filler, repetition of the schema, or unnecessary detail.

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?

Given that all parameters are optional, richly described in the schema, and an output schema exists, the description provides the remaining operational context: default date range, currency conversion, per-store mode, and the plan requirement. Nothing essential for correct invocation 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%, so the baseline is 3. The description lightly reinforces per_store and reporting_currency, but it does not add meaning beyond what each parameter's schema description already provides.

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 verb ('get'), a concrete resource ('combined profit and loss across every linked store'), and key qualifiers: date range, currency conversion, and the per-store breakdown option. It clearly distinguishes itself from single-store P&L tools by emphasizing 'across every linked store' and 'combined'.

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 a clear prerequisite ('Requires a plan covering more than one store') and explains when to set per_store. It does not explicitly point to an alternative tool for single-store P&L, so the when-not-to-use guidance is implicit rather than fully explicit.

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