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

With no annotations, the description carries the full burden; it does add real context by disclosing the plan gating ('Pro and Data plans'), which an agent needs to know before calling. However, it does not state how 'biggest' is ranked, whether results are sorted, or how 'main lines' are selected, leaving key behavioral traits undisclosed.

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?

A single front-loaded sentence with no filler; the market types and plan restriction are packed in efficiently. It is a sentence fragment rather than a full statement, but nothing is wasted.

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?

No output schema, no annotations, and no parameter documentation, yet the description omits the ranking criterion, default result count, and allowed values for period and competition. An agent could call it, but not confidently predict or shape the response.

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 0% across three parameters, and the description says nothing about limit, period (ft/h1/h2/q1-q4), or competition. Only 'upcoming games' loosely hints at the time dimension, so the description fails to compensate for the undocumented schema.

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 names the specific resource (cross-bookmaker differences on main lines for upcoming games) and enumerates the market types returned (moneyline, handicap, totals), which clearly separates it from get_game and list_games. It is a noun phrase without a leading verb, but the resource and scope are 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?

Usage is only implied: 'biggest cross-bookmaker differences' signals a discovery/comparison use case, and 'upcoming games' narrows the scope. There is no explicit when-to-use, when-not-to-use, or routing to any of the sibling tools.

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