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

Annotations already cover the safety profile (readOnlyHint, openWorldHint), and the description adds meaningful behavior the annotations do not: the source is a static pair directory rather than live data, results are ordered by market-id, and filters apply specifically to that directory. That data-staleness and ordering context is exactly the kind of disclosure that helps an agent calibrate trust in the output.

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?

Three tight sentences, front-loaded with what the tool returns and how it is ordered, then filters, then exclusions. No filler, and the most decision-relevant facts come first.

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?

With an output schema present, return-value detail can be omitted, and the description still covers source, ordering, filter scope, and the Kalshi/cross-venue gap. The only shortfall is the absence of sibling routing, which leaves the agent to infer where this sits among the many comparison tools.

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 side, family, and amount_usd. The description only confirms that side and family filter the pair directory and is silent on amount_usd (the budget/taker-fee parameter), so it adds little beyond structured data. 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 ('List independent Polymarket quotes from the static pair directory') plus an ordering guarantee, which is concrete. It doesn't name the closest siblings (compare_executable_quotes, get_executable_quote, list_arbitrage_candidates), so an agent must still infer the boundary between 'list quotes' and 'compare executable quotes', but the object of the tool is unambiguous.

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 tells the agent what is NOT included (Kalshi prices, cross-venue rankings) and redirects to an external URL for human comparison, which is useful exclusion guidance. However, it never says when to prefer this over the many sibling listing/quote tools, so the when-to-use decision is left implied.

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