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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the agent knows this is a safe, side-effect-free pure computation. The description adds that pattern repeat and waste are factored in, which is useful behavioral context, but nothing about rounding conventions or assumptions. With annotations carrying the safety profile, a 3 is appropriate.

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?

Front-loaded with the core action and kept to a handful of short sentences. Minor waste: 'Returns roll count and length needed' duplicates information already available in the output schema, and 'Inputs:'/'See ...' fragments are terse but readable.

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 explained, and all four parameters are documented in the schema. The remaining gaps are material for selection: no differentiation from calculate_wallpaper and a phantom 'pattern repeat' input, so the definition is not quite complete for correct invocation.

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%, so the baseline would be 3, but the description actively misleads: it lists 'pattern repeat' as an input even though the schema has no such parameter and additionalProperties is false, and it says 'walls m²' where the schema actually takes perimeter_m and height_m. An agent trusting the prose would try to supply a parameter that does not exist.

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 gives a specific verb and resource ('Compute wallpaper rolls for a room') and names the domain factors (pattern repeat, waste), so the purpose is unmistakable. However, it does nothing to distinguish this tool from the near-identical sibling calculate_wallpaper (nor from calculate_curtain_fabric / calculate_paint_needed), which is exactly the differentiation this crowded sibling list demands.

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 for renovation' is the only usage cue and it is far too broad to route an agent. There is no when-to-use/when-not, no statement of prerequisites, and no mention of calculate_wallpaper, which appears to be a competing wallpaper calculator. The agent is left to guess which of the two to call.

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