affiliate_webgains-advertiser_get_earnings_summary

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

There are no annotations, so the description carries the full burden. It does disclose that it returns an EarningsSummary including oldestUnpaidAgeDays and that results can be broken down by programme and status, which is useful. But it says nothing about auth, read-only nature, pagination behavior (despite limit/cursor params), or error semantics, so it's a 3.

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?

Two sentences, no fluff, front-loaded with purpose. It packs a lot of useful info without wasted words.

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 tool with 9 parameters, no annotations, and no output schema, the description is thin. It covers the main purpose and one return field, but misses parameter documentation, pagination, and required params. An agent would likely need to guess or leave out crucial parameters like brand.

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 0%, so the description must compensate. It explains the date window (from/to), programme and status filters implicitly, but the required 'brand' parameter is not mentioned, and limit/cursor/maxAgeDays/minAgeDays are left unexplained. This leaves the agent unable to correctly populate 4 of 9 parameters from the description, so a 2.

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?

The description opens with 'Summarise earnings on Webgains (advertiser) across a date window, with breakdowns by programme and by transaction status,' which clearly identifies the action, resource, and scope. The parenthetical '(advertiser)' distinguishes this from the non-advertiser webgains variant, and the mention of breakdowns sets expectations. A 5 is warranted.

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?

It explicitly says 'Use this when the user wants a single-figure answer plus context' with a concrete example, which is a clear usage guideline. It also recommends pairing with 'list_transactions to drill into the underlying records,' naming an alternative tool. However, it doesn't explicitly state when to prefer list_transactions over this or what not to use it for, so a 4.

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