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 is covered by structured data. The description adds no behavioral context beyond that: it does not say whether the recommendation is deterministic, whether it can return nothing for a given priority, or how strongly the priority constrains the result.

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 with zero filler or redundancy. Its brevity is a virtue structurally, even though the same brevity causes the specification gaps noted elsewhere.

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 a read-only one-parameter tool is inherently low complexity. Still, an agent lacks any note on deterministic behavior, empty-result handling, or how this relates to list_materials — small gaps that matter for correct selection.

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 0% for the single required parameter, so the description would need to compensate — but it only restates the parameter name as "project priority." The enum values (brandschutz, robust, effekt, nachhaltig, feuchtraum) are self-explanatory in German, yet the description adds no meaning about interpreting them or whether exactly one priority is expected.

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?

"Recommend a Caspar material" gives a specific verb and resource, and "based on a project priority" names the input basis, so an agent knows exactly what it produces. It stops short of distinguishing itself from the sibling list_materials, which is the obvious browse-all alternative, so a 4 rather than a 5.

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?

There is no explicit when-to-use or when-not-to-use guidance and no named alternative; the agent must infer that this is for priority-driven selection rather than browsing the catalog. The sibling list_materials is never mentioned, so routing between the two is left entirely to inference.

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