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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds meaningful behavioral context: it states that calling without a code returns all codes of the year that have published structural features, and that results include the decomposed conditions. This goes beyond the annotations.

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 both carry essential information: the first defines the main purpose, the second clarifies the optional no-code behavior. No filler or redundant restatement of the tool name/title.

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 read-only tool with two optional parameters, an output schema, and full schema descriptions, the description is complete enough for an agent to invoke it correctly. It covers the main behavior, the optional argument semantics, and the read-only/idempotent nature via annotations.

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 the parameters are already fully documented. The description adds the contextual behavior that omitting the code returns all codes of the year, but it does not add new parameter-level meaning beyond what the input schema already provides.

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 clearly states the tool's purpose: it returns OPS structural features checked by the Medical Service for an OPS code, including the conditions into which they are decomposed. The legal reference and the explicit resource ('Strukturmerkmale') distinguish it from the sibling get/search tools even without naming them.

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 description implies when to use the tool: when you need OPS structural features and their conditions. It also explains the no-code behavior, but does not explicitly compare with alternatives such as lg_get or lg_search or state 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.