ebay_get_order_earnings

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

Goes far beyond the readOnlyHint annotation: it discloses the required optional OAuth scope and the fact it is not requested by default, the seller eligibility constraints (US/CN/HK, USD payouts), and the EU/UK Digital Signature caveat that the server does not support. These are exactly the operational details an agent needs before calling.

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?

Functionally front-loaded with the primary purpose and returned fields, then the access constraints. The scope/signature caveats are dense but necessary; a single run-on sentence at the end slightly reduces readability.

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 read-only, no-output-schema tool with fully documented parameters, the description covers the purpose, scope/auth prerequisites, defaults, and known platform limitations. Nothing an agent needs to invoke it correctly 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 description coverage is 100%, so the schema already documents all five parameters, including format examples and defaults. The description restates the same semantics (date range, limit/offset, sort) without adding syntax or edge-case detail beyond the schema, landing at the baseline.

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 (Get) and resource (order-level earnings from eBay Finances API) and enumerates exactly what fields are returned (gross amount, expenses, refunds, net earnings). This makes it distinguishable from siblings like ebay_get_order_earnings_by_id and ebay_get_order_earnings_summary, which address a single order and a summary view respectively.

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 explains filtering, paging, sorting, and scope prerequisites, which define when it can be used. It does not explicitly name alternatives (e.g. use the by-id variant for a single order) or state exclusions, so it falls short of the top score.

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