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

Annotations already provide readOnlyHint, idempotentHint, and openWorldHint, so the description does not need to restate safety. It adds useful behavioral detail: the result appears in 'focus', includes code lists and dates, and omitting the code returns the top-level structure. This goes beyond the annotations and does not contradict them.

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 a single focused sentence with no filler. It leads with the primary return value, then the additional contained information, and ends with the fallback behavior. Every clause earns its place.

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 getter with two optional parameters, an output schema, and annotations covering safety, the description is nearly sufficient. It explains fallback behavior and return contents, and the schema handles year defaults. The only gap is not explicitly routing agents to seg4kde_search when they need to locate a recommendation without knowing its number, but this is not a block to correct invocation.

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 baseline is 3. The description reinforces the no-number behavior already present in the code parameter's schema description, but it adds little new semantic detail about the year parameter or value formatting. The schema already covers the important defaults, so the description provides adequate but not exceptional parameter context.

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 ('Liefert') and a specific resource ('SEG-4-Kodierempfehlung'), and details what is returned: full text, publication/modification dates, and ICD/OPS/DRG codes. The no-number fallback to the top-level structure further clarifies the tool's scope. This is clearly distinguishable from sibling search tools because it retrieves a full recommendation rather than searching.

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 one explicit usage condition: calling without a number returns the top-level hierarchy, and the schema clarifies that leaving year blank uses the latest year. However, the description does not say when to prefer seg4kde_search for finding a recommendation when the number is unknown, nor does it name alternatives or exclusions. The usage context is implied rather than fully explicit.

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