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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the date boundary is UTC-based and inclusive of today, and series filtering only applies 'when the source labels series', which warns of imperfect filtering. It doesn't mention rate limits or data freshness, keeping it below 5.

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?

Front-loaded purpose sentence is good, but the Args section duplicates the input schema word-for-word and contributes nothing, while the Returns section restates an output schema that already exists. Roughly half the text fails to earn 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?

An output schema exists, so re-explaining return fields is redundant but harmless; the description's real contributions—UTC/today-inclusive boundary and the source-labeling caveat for series filters—fill gaps the schema can't express. Nothing critical is missing for a read-only list tool.

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 Args block repeats the schema's parameter text almost verbatim (limit 1..200, offset paging, optional series_id), adding no new semantics. Baseline 3 is appropriate for a fully documented schema with no compensating detail.

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 and resource ('Return the upcoming match schedule') plus its optional filter, which separates it from cricket_get_live_matches (in-progress) among the siblings. It stops short of naming those siblings explicitly, so the differentiation is inferable rather than stated.

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 description clarifies the consequence of omitting series_id ('returns all upcoming fixtures across all active series') and the 'today (UTC) or later' window, which implies when the tool applies. However, it never tells the agent when to prefer it over cricket_get_live_matches or football_get_fixtures, and gives no exclusions.

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