list_tax_rates

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

Annotations already mark the tool as read-only (readOnlyHint: true), so the description doesn't need to restate safety. It adds value by explaining that each rate defines tax for a region and that filtering is possible, which are useful behavioral details beyond 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?

The description is concise, with three short sentences that first state the primary purpose, then a usage tip, then a domain note. Every sentence earns its place with no redundancy or filler.

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 simple list endpoint with four fully documented parameters and no output schema, the description covers purpose, filtering, and domain semantics. It does not mention pagination or field selection, but these are implied by the schema defaults, so the overall context is adequate without being exhaustive.

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 schema already documents all parameters. The description adds a small note about filtering by 'class', which aligns with the 'class' parameter, but doesn't elaborate on the meaning of other parameters or their interaction beyond the schema.

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 clearly states the action ('List tax rates') with a specific resource, and adds context about filtering by class and regional scope. This distinguishes it from sibling tools like list_tax_classes (which lists classes) and get_tax_rate (which retrieves a single rate).

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 provides usage context by illustrating how to filter by tax class ('Filter by tax class to see rates for a specific class'). It does not explicitly name alternatives or exclusions, but the intended use case is clear from the phrase and the tool's name.

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