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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description still adds two genuinely non-obvious behavioral facts — results are ordered newest first and totals are in minor units — but says nothing about pagination behavior, result volume, or what happens when organizationId points at a gym the caller doesn't belong to.

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?

Two short sentences with no filler, and the core identity of the tool is front-loaded. The wording 'Invoices the coach ... issued' is slightly contorted but costs almost nothing.

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 read-only, three-parameter list tool with no output schema, the definition covers scope, ordering, and currency units — the facts an agent most needs to interpret results. Pagination semantics are the main omission, and the schema's defaults and maximums partly cover that.

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 0%, so the description must carry parameter meaning; it explains organizationId as the gym-scoping switch, which is real value. However limit and offset are never mentioned, leaving two of three parameters undocumented in both schema and description.

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 resource (invoices) plus the issuing party ('the coach, or a gym with organizationId'), which implicitly separates it from client-side siblings like list_client_invoices or list_payments. It does not name any sibling explicitly, so the differentiation is inferable rather than stated.

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 parenthetical 'with organizationId' is the only conditional guidance and it is about scoping, not about when to choose this tool over list_client_invoices, list_organization_payments, or list_payments. Usage is implied by the seller-side framing but no alternatives or exclusions are given.

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