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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds the useful behavioral distinction between forward-looking (tonight) and retroactive (this gameweek) data. It says nothing about freshness, refresh cadence, or result size, which are the remaining behavioral unknowns.

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 usage cue comes first and the scope details follow. Slightly denser than ideal because the two view modes are packed into one colon clause rather than separated, but nothing is wasted.

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 two-parameter, zero-required read tool with full schema coverage and complete safety annotations, the description covers what the tool answers and when. The only gap is behavior of the names filter and what fields come back, but no output schema exists so return-value detail is a minor omission.

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%, with the 'view' parameter fully documented including its default and the meaning of both modes, so the baseline is 3. The description echoes the same tonight/gameweek split but adds no syntax and never mentions the 'names' filter, so it does not exceed the schema.

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 a specific resource (FPL price rises and falls) and the exact data it returns: players likely to change tonight or changes already made this gameweek. It is clearly distinguishable from every sibling tool, none of which concern pricing. It stops short of an explicit verb+scope statement naming the alternative, so a 4 rather than a 5.

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 leading 'Use this for FPL price rises and falls' gives an unambiguous use case that an agent can match to a user question about price movement. It supplies no exclusions or named alternatives, which is the only thing separating it from a 5.

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