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

Annotations already declare this as a non-readonly, destructive, idempotent mutation. The description adds genuinely new context beyond that: the plan gate on hiding, and the agent-boundary rule that it may toggle the switch but never select a plan. It omits any note on reversibility of the badge change, but the added constraints are substantive.

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?

Two very short sentences, front-loaded with the action before the constraint. Nothing is padded, though the extreme brevity is closer to under-specification than disciplined concision.

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 return values need not be described, and the plan/agent constraints are covered. For a destructive, idempotent mutation the description still leaves the boolean polarity undocumented, which is the one thing an agent must get right to call it correctly.

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 0% for the single "show" boolean, so the description must carry the semantics. It never states that show=true displays the badge and show=false hides it; the agent must infer this from "Flip the badge" and the phrase about hiding. That is a meaningful gap for the only parameter.

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?

"Flip the badge" names a specific mutation action, and the title supplies the missing object (the Powered-by-Fillo badge), so together the operation is unambiguous. It does not, however, distinguish itself from the sibling fillo_get_branding within the description text itself.

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?

"Hiding needs the Everything plan" is a real precondition that tells the agent when the hide direction will fail, which is useful usage context. No alternative tool is named (e.g. fillo_get_branding for reading), so the routing guidance is only partial.

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