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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety needs no restatement. The description adds genuine behavioral context beyond that: it discloses the inputs consumed (room area), the 2x2 ft tile assumption, and a 5 percent cut-waste factor, which shapes how the result should be interpreted.

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 carrying the tile size, room shape constraint, and waste factor with no filler. Nothing could be removed without losing a real constraint.

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 usefully signals what comes back: a tile count, the room area, and a cut-waste reminder. It does not clarify rounding behavior or whether the waste allowance is already folded into the count, leaving a minor ambiguity for a tool this simple.

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 (length, width in feet) are fully documented in the schema, so the description need not explain units. It recasts them as 'room area' but adds no syntax or constraint detail beyond the schema, so the baseline of 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 (count) and resource (2x2 ft ceiling tiles) plus scope (rectangular room). An agent can distinguish it from siblings such as roofing, insulation, and square_footage without inspecting 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?

Use is implied by the domain: you call it when you need ceiling tile counts for a rectangular room. However, no explicit when-to-use condition is stated and no alternative sibling (e.g., roofing for shingles, square_footage for raw area) is named or excluded.

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