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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context beyond them: results are limited to open listings, sorted soonest first, and include prize plus a worth-a-sprint verdict. It omits pagination behavior and how the verdict is derived.

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?

A single front-loaded sentence with no filler; the filter, sort order, and return highlights arrive in the right order. It is efficient, though it spends words on the informal 'worth a sprint' phrasing instead of documenting parameters.

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 list tool with no output schema, the description gives a usable sketch of results but leaves limit/pagination and min_prize_usd entirely unexplained. Adequate as a minimum-viable definition, with clear gaps for a 3-parameter tool.

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 0% for all three parameters, so the description carries the full burden — but it only gestures at 'N days' without naming the parameter, its default (7) or its 0-60 bound, and never mentions limit or min_prize_usd at all. An agent cannot infer the prize filtering capability from the text.

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 ('Open listings whose deadline is within N days') plus the ordering ('soonest first'), which clearly separates it from best_opportunities and whats_new. It stops short of naming an alternative sibling, so it lands at 4 rather than 5.

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 deadline-window framing implies the use case (find time-sensitive listings) but there is no explicit when-to-use/when-not guidance and no pointer to a sibling for other browsing needs. Usage must be inferred from the name and the 'N days' filter.

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