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 covered. The description adds genuinely useful behavioral context by enumerating what is returned (positions, form, goals, this season's meeting, next fixture date) and by fencing off betting advice, though it says nothing about pagination, latency, or error behavior.

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?

Four short clauses, front-loaded with the purpose, then the example trigger, then the payload, then the scope limit. The redundant 'Form Guide.' opener is the only filler, and every other phrase carries information.

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 must convey what comes back, and it does so by listing positions, form, goals, head-to-head meeting, and next fixture date. The only gap is that the legacy team1/team2 aliases and the country side-effect (US Eastern kick-off lines) are left entirely to the schema.

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 the schema already documents home, away, country, and the legacy team1/team2 aliases, which sets the baseline at 3. The description adds no parameter-level meaning — it never clarifies the home/away roles, the legacy alias behavior, or what the country flag does — so it cannot rise above baseline.

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 operation (comparing two clubs side by side) on a specific resource (two teams about to meet), and the sample query 'Arsenal v Leeds, how do they compare?' makes the intent unmistakable. It is clearly distinguishable from formguide_get_team (one club) and formguide_get_table (league-wide) without opening any schema.

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?

It gives a concrete trigger scenario ('Arsenal v Leeds, how do they compare?') and states the scope boundary 'stats only, not betting advice'. It stops short of naming alternatives such as formguide_get_fixtures or formguide_get_team for single-side questions, so there is no explicit when-not guidance.

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