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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered structurally. The description adds useful context about payload contents (score, minute/period, TV channels 'where known'), which also flags that channel data may be absent — but it says nothing about freshness or result volume.

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 temporal scope and return contents are stated immediately and nothing is repeated from the schema.

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 no output schema, the description usefully characterizes the return shape (score, minute/period, channels where known), which is exactly what an agent cannot get elsewhere. It is nearly complete for a simple read tool; only edge behaviors like empty results or freshness remain unaddressed.

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 sport (with its 'see list_sports' pointer), lang and league_id are already fully documented in the schema. The description adds no parameter-level meaning beyond that, so the baseline 3 applies.

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 (matches) with an unambiguous temporal scope ('in play right now'), which cleanly separates it from the scheduled/historical siblings like get_matches, get_match and get_match_details. It also names the payload (score, minute or period, TV channels).

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 implied by 'right now' — an agent can infer it should call this for currently active matches rather than completed ones. However, no alternative tool is named and there is no explicit when-not guidance (e.g., use get_matches for fixtures).

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