ebay_update_flat_shipping_rules

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

Annotations already declare the mutating-but-idempotent profile, and the description adds real value on top: the 204 No Content response, the need to re-query to confirm, and the sell.account requirement. Minor gap in not detailing failure/partial-update behavior.

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?

Three compact sentences, each carrying distinct information (what, ID sourcing, header/return/auth). Dense but front-loaded and free of 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 two-parameter, deeply nested request with no output schema, the description covers the mutation effect, the header placement, the auth scope, and the return/confirmation path. Only minor behavioral detail (error handling) is absent.

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 100%, so the schema already documents both the marketplaceId header semantics and every nested rule field. The description only restates that combinedShippingRuleId comes from ebay_get_combined_shipping_rules, adding little 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?

States a specific verb (Update) plus the exact resource (flat-rate combined-shipping rules and/or combinedDuration) and the underlying API operation. It clearly separates this from the sibling create_flat_shipping_rules by specifying it updates existing rules.

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?

Tells the agent to obtain rule IDs from ebay_get_combined_shipping_rules and to confirm the result with the same tool, and notes the required sell.account scope. It gives clear context but does not explicitly contrast when to choose create vs update (that hint only appears in the schema).

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