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

Beyond the readOnlyHint annotation, the description discloses substantial behavioral detail: no-vig probabilities are passed through unmodified, the overround is ~8.4%, only 'exclusive' markets partition the outcome space, and decided live matches close their moneyline rather than returning missing data. These caveats prevent serious misuse and add real value beyond the annotation.

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?

The description is longer than average, but every sentence earns its place: core definition, use cases, data semantics, market-structure warning, and explicit non-uses. It is front-loaded with the essential purpose, and the caveats appear in logical order without redundancy.

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 odds tool with no output schema, the description is remarkably complete. It explains what is returned (open markets, decimal prices, no-vig probabilities), how to interpret them, current-only freshness, and key edge cases like closed moneylines and non-exclusive markets. An agent has enough context to call this tool correctly and interpret results safely.

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%, so the baseline applies: the input schema already fully documents tier, limit, and sport. The description itself adds little parameter-specific meaning, though it reinforces context like limit trimming and sport vocabulary through other parts of the definition. No deduction is warranted because the schema is already strong.

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?

The description opens with a specific verb and resource: 'Current live (in-play) odds for this product's board: every fixture with its OPEN markets, decimal prices and the no-vig probability on each selection.' It also distinguishes itself from multi-book scanning, historical archives, and bet placement, making its scope unmistakable and clearly separate from siblings like get_prematch_odds.

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 explicitly lists intended use cases ('live odds displays, arbitrage or middles checks against another book, in-play models and feature engineering, no-vig fair value, and agent workflows that need current prices') and gives explicit exclusions ('Not a multi-book scanner', 'Not a historical archive', 'Not a bet-placement tool'). It also points to list_sports and get_coverage as alternatives for sport vocabulary, giving an agent clear routing guidance.

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