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

Annotations already declare readOnly=true, idempotent=true, openWorld=false, destructive=false, so the safety profile is fully covered. The description adds useful data semantics — freshness ('live') and that results carry a 1-4 journalistic reliability grade — but says nothing about result volume, empty/no-rumour behavior, or coverage limits.

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 resource and grading scheme come first. It is efficient, though quite terse for a tool with two filter dimensions.

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?

There is no output schema, so the description is the only place return shape could be described — it does not say what a rumour record contains (club, player, source, tier, date). For a low-complexity read-only fetch this is acceptable but leaves a real gap.

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 coverage is 100% and both parameters are documented in the schema, including the enum and its direction (1 = highest reliability). The description reinforces the tier concept but adds no syntax or semantics beyond that, 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?

Specific verb+resource+scope: 'Retrieve live 2026/27 Premier League transfer and managerial rumours graded Tier 1-4 by journalistic reliability.' The tier-grading qualifier helps separate it from get_fpl_transfer_trends, but the description never names that sibling, so the differentiation is left for the agent to infer.

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?

Usage is only implied by 'live' rumours and the optional filters; there is no explicit when-to-use, when-not-to-use, or alternative named (e.g. get_fpl_transfer_trends for FPL-side movement). An agent can pick this tool for a rumours query, but must reason about edge cases itself.

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