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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile needs no restating. The description adds genuine context beyond that: what the computation yields (per-step calculators run in the guide's order, waste and order quantities, person-hours, both unit systems). Scoring opportunistically, it also sets an explicit scope boundary with "No prices; nothing sized," which prevents the agent from treating the result as a quote or a sized design.

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 sentences, front-loaded with the verb and resource, no preamble. The long enumeration of answer components is dense but each item earns its place by telling the agent what the response will contain, and the terse "No prices; nothing sized" fragment carries its weight as a scope limit.

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 an output schema present and 100% parameter coverage, the description need only orient the agent — which it does, including the unit-system behavior and the explicit exclusion of pricing and sizing. The one gap is the lack of any statement about prerequisites for the guide slug (i.e., the page must actually have a "Try the calculation" block), which is only implied by the schema's pattern description.

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 all six parameters, including the measurements map and its unit rules, are already well documented. The description's parameter-adjacent content ("on the figures given," "both unit systems," the guide's link opening on these figures) largely restates what the schema and its enum descriptions already say, so it adds little semantic leverage. Baseline 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?

The description gives a specific verb and resource: it runs a how-to guide's "Try the calculation" block with the caller's figures, and it enumerates what comes back (buy list with waste and order quantities, both unit systems, person-hours, a page link). It does not, however, distinguish itself from close siblings like run_example, run_example_live, or calculate, so the agent must infer the boundary between running a guide's block and running a calculator's worked example.

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?

Usage is implied by the framing — you invoke it when you want a named guide's built-in calculation evaluated on your own numbers — and the closing scope note "No prices; nothing sized" tells the agent this is not the tool for costing or sizing. But there is no explicit when-to-use statement, no named alternative for the pricing/sizing case, and no guidance on when run_example_live would be the better choice.

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