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

Without an output schema, the description fully explains the return shape: columns, column_types, rows, row types, depth, id alignment, hidden_zero_rows, filters, and no_data. It also discloses behavior like omitted zero rows and how errors/ignored parameters surface (absent from filters). This goes far beyond the readOnly hint and is exception detail for a reporting tool.

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 main action is front-loaded, and every sentence contributes operational detail. The description is dense but not verbose; it packs the essential output contract into a compact paragraph without filler. Structured enough for an agent to parse the key facts in order.

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 the absence of an output schema, the description provides a complete contract: it explains the row schema, value types, id semantics for summary vs detail, zero-row handling, filter verification, and no_data edge case. An agent can invoke this tool and interpret its response without needing to guess.

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%: the params object already names report_date, date_macro, aging_method, vendor, department. The description adds no new meaning about how to use these parameters beyond what the schema states; the extra details about filters relate to output behavior, not parameter semantics. Baseline 3 is appropriate because the schema carries the load.

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 opens with a clear verb-resource pair ('Generate the QuickBooks aged payables report') and goes on to detail the output structure. It distinguishes this tool from related siblings like get_aged_payable_detail by describing both summary and detail row semantics, and the name itself disambiguates payables from receivables.

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 tells you what the tool does but does not explicitly state when to choose it over get_aged_payable_detail or other aged reports. The sibling list hints at an alternative, but there is no direct guidance such as 'use this for the summary; use get_aged_payable_detail for line-level detail.' Usage context is implied from the name and report type but not made explicit.

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