Estimate shelf sag

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

readOnlyHint=true already tells the agent this is a safe calculation. The description adds the model assumptions (uniformly loaded, simply supported), which is genuinely useful for judging validity, but says nothing about units, whether the result is an estimate with error bounds, or what the tool returns.

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?

One sentence plus a short clause, with the core action and its modeling assumption front-loaded. No filler.

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?

For a 4-parameter calculator with no output schema and half the parameters undocumented, the description leaves real gaps: undefined material values, no units, and no indication of what the returned deflection looks like. It is workable but not complete.

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 only 50%: span and depth carry descriptions, but 'load' (enum light/books/heavy) and 'material' (default plywood_18) are undocumented in both schema and description. The description contributes no parameter meaning at all, so it fails to compensate for the coverage gap.

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 ('estimate deflection') and a precise resource scope ('uniformly loaded shelf, simply supported'), which no sibling tool covers. It does not name or contrast with siblings such as aikea_design, but the domain specificity makes overlap unlikely.

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?

'Useful for choosing widths/materials before designing' gives clear context for when to reach for this tool and implies the workflow step relative to aikea_design. It stops short of naming an alternative tool or stating when not to use it.

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