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

Annotations already declare idempotentHint=true and destructiveHint=false; the description adds real context on top — it names the mechanism ('dieselbe Übermittlungskennung erzeugt keine zweite Sperre'), i.e. that submission_key is the idempotency driver, and states that existing portal permissions and category assignments remain in effect. Useful non-obvious behavior, though it says nothing about failure modes or what happens on overlapping blocks.

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?

Three short sentences, purpose first, then persistence behavior, then the idempotency caveat — no padding and each sentence carries distinct information. Slightly under-structured in that the idempotency note could be tied explicitly to the submission_key parameter.

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 annotations cover the safety profile. The description supplies purpose, persistence semantics and idempotency; the only real gap is routing relative to the sibling block/special-day tools, which is not addressed.

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 are already documented in the schema, including the semantics of service_category_id and submission_key. The description adds no parameter-level detail beyond that (it never mentions service_category_id or the required date fields), so the baseline 3 is appropriate.

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?

Names a specific verb+resource ('eine Sperrzeit anlegen') scoped to 'den verbundenen Mitarbeiter', which is enough to separate it from the read/booking siblings. It stops short of naming its nearest siblings (coworking_staff_update_block, coworking_staff_delete_block, coworking_staff_create_special_day), so the agent must infer the boundary itself.

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?

Implies usage ('für den verbundenen Mitarbeiter' — this acts on the caller's own staff identity, not an arbitrary user), and the note that existing permissions/categories carry over hints at prerequisites. But there is no explicit when-to-use-this-vs-update_block-vs-create_special_day guidance and no stated preconditions.

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