ebay_create_calculated_shipping_rules

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

Annotations only declare readOnlyHint=false, so the description carries the rest of the load and does so well: it discloses the sell.account authorization requirement, that marketplaceId is transmitted as the X-EBAY-C-MARKETPLACE-ID header, and that a successful call yields 204 No Content with no body. It omits any error/failure behavior or rate-limit context.

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 dense but front-loaded paragraph that opens with the action and proceeds to body composition, auth, and verification. Every sentence earns its place, though the parenthetical API reference and enum-heavy phrasing make it slightly harder to scan than it could be.

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 mutation tool with no output schema and a deeply nested request body, the description covers what to send, which permission is needed, how the marketplace is transmitted, what a success response looks like, and how to verify the result. Nothing essential to correct invocation is missing.

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 coverage is already 100%, so the baseline would be 3, but the description meaningfully adds to it: it decomposes the shippingRules object into calculatedShippingRule (weight/item/cost-based discounts), calculatedHandlingRule, and combinedDuration, and explains the header mapping for marketplaceId. This goes beyond what the schema alone conveys.

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 verb and resource ('Create calculated combined-shipping rules') and scopes it to listings that use calculated shipping, which distinguishes it from the sibling ebay_create_flat_shipping_rules and ebay_create_promotional_shipping_rule. An agent can pick this tool without opening the schema.

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?

Gives clear context: it applies to listings using calculated shipping, requires the sell.account scope, and points to ebay_get_combined_shipping_rules as the confirmation step. It does not explicitly contrast with ebay_update_calculated_shipping_rules or state exclusions, so it stops 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.