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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered and the bar is lower. The description still adds real behavioral context: the squad is produced by an optimiser, respects a £100m budget, and obeys FPL squad rules, which tells the agent what the output represents. It omits return format/pagination, but that is secondary here.

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 that leads with the trigger condition and then the tool's scope. No filler or repetition of the tool name.

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 should ideally hint at what is returned (a list of players, formation, cost breakdown). It conveys the key constraints and the read-only, idempotent nature via annotations, which is sufficient to call the tool correctly, but the return shape is left implicit.

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 both parameters (gw, chip) and their defaults and enum values are fully documented in the schema. The description adds no syntax or format detail beyond saying the squad is 'for a gameweek', 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 verb (get), a specific resource (best FPL Wildcard or Free Hit squad), and scopes it further by naming the optimiser, the £100m budget, and FPL squad rules. This distinguishes it clearly from siblings like rate_my_team, get_my_team, and compare_players.

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 opening clause 'Use this when someone wants the best FPL Wildcard or Free Hit squad for a gameweek' gives a clear triggering context. It does not, however, name competing alternatives (e.g. rate_my_team or get_my_team) or state when this tool should not be used, so it stops short of a 5.

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