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

With no annotations, the description carries the full burden and does well: it discloses the price ($0.01 USDC on Base), that no account or API key is needed, and the sort order of results. It stops short of saying whether results are cached/live-realtime or what happens on payment failure, which keeps it out of the top band.

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?

Roughly three dense clauses, front-loaded with the 'Paid.' flag, then content, then the return fields, then payment/auth terms. No filler sentences, and the raw endpoint URL is the only mildly extraneous element.

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?

There is no output schema, so the description must enumerate return values — it does ('odds per outcome, volume, liquidity, end date, link'). Combined with the cost and auth statement, an agent can decide and call correctly with one optional parameter.

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 100% — the single 'limit' parameter already documents 'Markets, 1-50 (default 10)'. The description adds no syntax or default detail beyond what the schema provides, so the baseline of 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 ('Live Polymarket odds for nba markets') plus the ordering ('sorted by 24h volume'). The 'nba' scoping makes it trivially distinguishable from the sibling topic feeds like buy_pm_nfl, buy_pm_soccer and buy_polymarket without opening any schema.

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?

Usage is implied by the topic scoping — an agent knows to call this for NBA prediction-market data — but nothing states when to prefer buy_polymarket (generic) over this one, nor any precondition beyond the cost note. The leading 'Paid.' is a useful caution but not a routing rule.

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