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

With no annotations, the description carries the full burden and largely meets it: it discloses the paid model ($0.002 USDC on Base), the absence of account/API-key requirements, the sort order, and the shape of the returned payload. It omits rate limits, failure/refund behavior, and whether the limit applies before or after sorting.

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?

Front-loaded with the key qualifier 'Paid.' followed by scope, payload contents, price, auth posture, and endpoint — dense with no filler. The telegraphic fragment style and the raw URL, while useful, make it slightly less scannable than a well-structured sentence form.

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 single-optional-parameter read tool with no output schema, the description covers cost, auth, sorting, and returned fields — enough to invoke correctly. A brief note on pagination or the default market count would close the remaining gap.

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% — the single 'limit' parameter already documents its range (1-50) and default (10), so the description need not repeat it. The description adds only the sort key, not any additional semantics about how limit interacts with 24h-volume ordering.

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 resource ('Live Polymarket odds for nfl markets') with scope and ordering ('sorted by 24h volume'), and the enumerated return fields. Against siblings like buy_pm_nba or buy_pm_soccer, an agent can immediately tell this is the NFL-topic endpoint in the same family.

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 topic scope ('nfl markets') plus the paid, no-account framing implies when to use it, but there is no explicit when-not guidance and the generic buy_polymarket sibling is never referenced as the alternative for non-NFL topics. Usage is inferable rather than stated.

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