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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds the NF DTU 21 standard and notes that it returns ingredient weights, which is useful context. However, it does not clarify behavioral details like whether the mix ratio is mandatory or how defaults are handled.

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?

The description is short and front-loads the core purpose, which is good. However, one of its four sentences introduces a nonexistent parameter ('mix ratio'), and another points to list_bundles rather than focusing on invocation details. The false input sentence does not earn its place and actively harms conciseness.

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 the description need not explain return values, yet it does so correctly in broad terms. The critical completeness failure is the mention of an unsupported 'mix ratio' input instead of clarifying the actual single-parameter interface. For a simple calculator with full schema and annotation coverage, the misleading parameter reference leaves the description incomplete and potentially error-inducing.

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 for the single actual parameter (volume_m3) is 100%, so the baseline should be 3. But the description claims a second input, 'mix ratio,' which does not exist in the schema and is explicitly disallowed by additionalProperties=false. This creates a concrete risk that an agent will try to pass an unsupported parameter, undermining the otherwise clean schema.

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 states a specific verb and resource: compute cement, sand, gravel, and water for a given concrete volume. It names the standard (NF DTU 21) and the ingredient outputs, which helps distinguish it from simpler construction calculators like calculate_gravel_quantity. It stops short of explicitly contrasting with concrete-related siblings such as calculate_concrete_stairs.

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?

The guidance is limited to 'Use for construction projects,' which is broad and does not clarify when this tool is preferable to siblings like calculate_gravel_quantity or calculate_concrete_stairs. It points to list_bundles for related calculators but provides no exclusions or decision criteria for selecting this tool over alternatives.

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