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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the retrieval scope ('single ... by Id') but no additional behavioral context such as auth requirements, rate limits, or return caveats. No contradiction exists.

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?

One crisp, front-loaded sentence with no filler. It states the operation, the resource, the source system, and the key selector (Id) in minimal space.

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 single-entity fetch with fully documented parameters, the description provides the essential context. Since there is no output schema, a brief note about the returned TaxCode payload would make it fully complete, but this is a minor gap.

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%, and both 'id' and 'company' are clearly documented in the input schema. The description adds no parameter details, but the schema carries that burden effectively.

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 uses a specific verb and resource — 'Get a single tax code from QuickBooks Online by Id.' The 'single' and 'by Id' wording clearly distinguishes it from sibling list/search tools like search_tax_codes.

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 implies the right use case: fetch one tax code when you know its QuickBooks Id. It does not explicitly name alternatives such as search_tax_codes or state when not to use this tool, so usage context is only implied.

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