ebay_get_order_earnings_summary

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

Well beyond the readOnlyHint annotation, the description discloses prerequisites an agent cannot discover elsewhere: the sell.finances.earnings.read scope is not requested by default and requires adding to EBAY_OAUTH_SCOPES plus re-running consent, eBay grants it only to approved US/CN/HK sellers with USD payouts, and EU/UK sellers must configure EBAY_SIGNING_KEY_JWE and EBAY_SIGNING_PRIVATE_KEY for Digital Signatures. That is exactly the kind of failure-mode context annotations cannot carry.

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-loaded with the purpose, then defaults, then the auth/eligibility/signing requirements in decreasing priority. The sentences are dense and slightly run-on with nested parenthetical caveats, but essentially every clause carries operational information.

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, two-parameter tool with full schema coverage and no output schema, this covers everything an agent needs: what it returns (aggregated earnings), scope setup, seller eligibility, and the signing requirement for EU/UK. No material gap remains.

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 both parameters (filter and marketplaceId) are already fully documented with examples. The description's mention of the orderCreationDate range and past-year default restates the schema rather than adding syntax or constraint detail, so the baseline 3 applies.

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: 'aggregated order earnings from the eBay Finances API for orders created in an orderCreationDate range'. This is clearly distinguishable from ebay_get_order_earnings and ebay_get_order_earnings_by_id by the word 'aggregated', but the description never explicitly names those siblings or states how the result differs from the per-order endpoints.

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 solid usage context: the default when the filter is omitted (past year) and the eligibility gates (approved US/CN/HK sellers with USD payouts). It does not state when an agent should prefer this summary over the sibling per-order earnings tools, leaving that routing to the name alone.

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