ebay_get_billing_activities

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

Annotations already declare readOnlyHint=true, so the safety profile is covered and the bar is lower. The description still adds real context the annotation cannot: the sell.finances scope requirement and the mandatory Digital Signatures for EU/UK sellers with the two env vars to set. However it says nothing about response shape or result limits beyond paging, leaving a gap for a tool with no output schema.

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?

Front-loads the purpose, then stacks the filter constraint, paging/sort, and auth requirements in a tight four-sentence block with no filler. The signing-key sentence is long but carries non-obvious setup information, so it earns its 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?

Covers the auth scopes, signing requirement, mandatory filter, paging, and sort defaults – enough for an agent to construct a correct call without an output schema. The one missing piece is any indication of what an activity record contains, which matters because there is no output schema to fall back on.

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 baseline is 3; every parameter is already documented in the schema. The description restates the filter rules and paging/sort behavior without adding syntax or edge-case detail beyond what the property descriptions already provide.

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 (get seller billing activities – fees and credits) and names the source API (eBay Finances). That 'fees and credits' framing implicitly separates it from siblings like ebay_get_transactions or ebay_get_payouts, but it never explicitly says so despite a crowded sibling namespace.

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?

Lays out hard preconditions for a valid call: exactly one filter criterion (activityId, listingId, orderId, or a transactionDate range starting within 120 days), plus paging and sort conventions. It gives clear context for use but no explicit statement of when a sibling (e.g. ebay_get_transactions, ebay_get_seller_funds_summary) would be the better pick.

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