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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so safety and idempotency are known. The description adds that probabilities come from a free Dixon-Coles model and are only present 'when published', which is useful conditional context, but it stays shallow on data freshness or rate limits.

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?

One dense but well-structured sentence with the main action front-loaded and the input flexibility tacked on with examples. No wasted words, though the long trailing clause could be split for readability.

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?

Complete for a read-only list tool with full schema coverage and rich annotations. It clarifies the probability source and condition, which is important for interpreting output, though it does not mention pagination or return shape (no output schema exists, but the description sufficiently frames what fields appear).

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 parameters (days, lang, competition) are already fully documented. The description adds value on competition input flexibility (name, abbreviation, id) and points to list_competitions, but otherwise the schema does the heavy lifting, so baseline 3 is appropriate.

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 (Lists), resource (upcoming matches of one competition), and scope (over the next days, with 1X2 probabilities). Distinguishable from siblings like find_match or get_match_probabilities by focusing on a forward-looking competition-level list.

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?

Implies when to use it – for upcoming fixtures of a given competition with probabilities when published. Names list_competitions as the source for ids, but does not explicitly state when not to use it versus find_match or get_match_probabilities.

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