ebay_get_billing_activities

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

Beyond the readOnlyHint, it discloses genuine behavioral traits: required OAuth scope, pagination via limit/offset, sort default (newest first), and critically that eBay requires Digital Signatures on Finances calls for EU/UK sellers which this server does not add — a failure condition an agent must know. This is substantial added context the annotations don't 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?

Purpose and scope are front-loaded, followed by the filter requirement, pagination/sort, and auth/signature caveats in compact sentences. Every sentence carries operational information with no 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?

Covers purpose, filtering, pagination, auth scope, and a real environmental caveat for a 5-parameter read tool. The one gap is that no output schema exists and the description doesn't hint at the return shape, but for a paginated read under readOnlyHint, the definition is otherwise complete.

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 all five parameters including filter patterns and sort semantics. The description largely restates the filter-criterion rule that the schema already encodes, adding little beyond it. Baseline 3 is appropriate when the schema does the heavy lifting.

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+resource ('Get seller billing activities (fees and credits)') and names the source API (eBay Finances). The parenthetical clarifies what 'billing activities' means, distinguishing it from sibling financial reads like ebay_get_transactions, ebay_get_payouts, and ebay_get_order_earnings.

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 concrete operational constraints: exactly one filter criterion required, allowable criteria listed, 120-day window limit, and the sell.finances scope requirement. It stops short of explicitly routing to alternative tools (e.g. when to prefer get_transactions), so it's clear context without named alternatives.

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