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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine context the annotations don't carry: default sort order ('newest first') and a 2-credit cost. It says nothing about pagination mechanics or result volume beyond what the schema's offset field implies, so it stays at a solid 3 rather than fully informative.

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 sentences, zero filler. Purpose and filters come first, disambiguation second, cost last — a sensible front-loading for a listing tool.

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 10 parameters, no required fields, high schema coverage, a rich annotation set and an output schema, the description covers the essentials: scope, alternatives, ordering and cost. It could do slightly more on paging behavior given a limit/offset pair, but nothing critical is missing.

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 90% and the enum-filled stage/league/season/status fields are documented in-schema. The description echoes the filter dimensions (season, stage, date, date range, club) but adds no syntax, interaction rules, or defaults beyond those; baseline 3 is appropriate given the schema does the heavy lifting.

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 (list) and resource (fixtures and results), enumerates the filter dimensions, and specifies the default ordering ('newest first'). It is clearly distinguishable from get_schedule and get_game, which are named in the same sentence.

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?

Explicitly routes the agent: get_schedule for upcoming fixtures with lines, get_game for a single match in full. It also discloses the credit cost, which is a real decision input when an agent chooses among tools.

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