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

Goes well beyond the readOnlyHint/openWorldHint annotations by disclosing the billing model: $0.002 in USDC per successful call, paid via x402 on Base, Solana or Arc, with failed calls not charged. That cost/auth context is decision-relevant and rarely stated. It stops short of describing the x402 payment handshake, entitlement/settlement failures, or rate limits, so it is strong but not exhaustive.

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?

Single front-loaded sentence that identifies source and content first, then enumerates inputs, then pricing — every clause carries information and nothing is padded. It is dense and slightly run-on (parenthetical book list, trailing price clause), which costs a point versus a cleanly broken structure.

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 and annotations covering safety, the description only needed to add inputs, content scope and cost — and it does all three. Remaining gaps are edge behavior: what happens when a date has no slate, whether payment failure blocks the call, and pagination/interaction with the limit 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%, with date format, league list, market options and defaults already documented in the schema, so the baseline is 3. The description reinforces the league set and market vocabulary but adds no new semantics (no date-range behavior, no interaction between market and output fields) beyond what the schema supplies.

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?

Names a concrete data product (US sportsbook odds comparison from SportsbookReview), the exact inputs that scope it (league, market, optional date), and the output inventory (teams, start time, venue, consensus pick percentages, opening/current lines and prices from named books). That content signature — multi-book comparison plus public consensus percentages — lets an agent separate it from single-book siblings like the Pinnacle or VegasInsider tools 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 only implicit: supported leagues and markets suggest when the tool fits, but there is no explicit 'use this when' statement, no exclusions (e.g. in-play/live odds, non-US books, props), and no named alternative among the many odds and scoreboard siblings. An agent must infer routing from the league/market vocabulary alone.

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