firestarter_set_shipping_policy

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

Annotations already indicate readOnlyHint=false and destructiveHint=false, so the description is not burdensed with basic safety disclosure. It adds valuable behavioral context: the distinction between the three modes, the automatic inclusion of the home country in 'list' mode, and the fact that sanctioned/embargoed destinations always stay blocked. It does not mention reversibility or overwrite behavior, but the provided context is strong.

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 front-loaded with the core purpose and then provides a usage scenario and mode details. It is somewhat long but every sentence earns its place (usage trigger, mode explanations, embargoed destinations, listing ID reminder). No wasteful repetition.

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 tool's complexity (4 parameters, 3 modes, no output schema), the description covers the modes, parameter interplay, and the sanctioned-destination caveat. It does not mention return values or success indicators, but with no output schema that is not a strict requirement. It also doesn't mention permissions or side effects, but for this mutating tool the description is sufficiently complete for an agent to invoke it correctly.

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?

The schema already has 100% parameter coverage with descriptions, so the baseline is 3. The description adds value by explaining mode semantics with concrete examples ('['CA','GB','AU']'), clarifying that the ship-from country is automatically included in 'list' mode, and noting that 'exclude' applies only to 'worldwide'. This goes 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 opens with 'Set where a seller is willing to ship a listing,' which is a specific verb+resource statement. It clearly distinguishes from siblings by focusing on setting a listing's shipping policy, not options, estimates, or shipping an order. The use case (checkout failure due to seller not shipping to destination) adds concrete context.

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 a clear trigger: 'Use this when a buyer wants delivery to a country the listing does not yet cover... or whenever the seller wants to change their shipping reach.' This is explicit guidance on when to use the tool. It does not name alternatives or state when not to use it, so it falls short of a 5.

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