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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=true, and destructiveHint=false, so safety and repeatability are covered. The description adds behavioral context by specifying that the data is live/in-play and enumerating the current fields returned, which helps an agent understand freshness and output shape. It does not discuss auth needs or rate limits beyond the schema.

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?

Two short sentences plus one compact example, front-loading what the tool returns. There is no filler or repetition; every element earns its place.

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 simple, single-parameter read tool with rich annotations and full schema coverage, the description supplies the missing output context (the live fields returned) and needs no output schema. No material gaps remain for correct invocation.

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% and the single required parameter _apiKey is fully documented in the schema, including where to get a token and free-plan limitations. The description only repeats an example call and adds no semantic meaning beyond the schema, so the baseline of 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?

The description names the exact resource and scope: live in-play soccer matches with current minute, state, teams, and running score. It is specific enough to distinguish from a generic fixtures tool, but it never names the sibling sportmonks_fixture or sportmonks_fixtures_by_date to make routing fully explicit.

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 phrase 'live in-play ... now' implies the tool is for real-time match state rather than historical fixtures, but there is no explicit when-to-use guidance, when-not-to-use guidance, or named alternative. An agent can infer the context, but must rely on inference.

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