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

With no annotations, the description carries the full burden and discharges it: it declares the accountant role and that the payload is personal data (auth implication), states there is no server-side filtering and no paging, notes one row per employee including left employees, explains current_contract is null when none is in force, and flags the three-state ahv_pensioner_allowance_waived pitfall that blocks the AHV/FAK declaration.

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?

Front-loaded with purpose and scope, then return shape, then caveats. Sentences are information-dense and each earns its place, though the multi-paragraph layout is longer than strictly necessary and the field enumeration could be tightened.

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?

With no output schema and no annotations, the description does the work by enumerating the returned fields (employee_no, display_name, address, ahv_number, birthdate, qst_liable, iban, current_contract, readiness) and their null semantics. Only the missing parameter explanation keeps it from being fully complete.

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?

The schema has 0% description coverage on the single required company_id, and the description never mentions or explains that parameter — it only implies company scoping via 'the payroll master data'. With low coverage the description is expected to compensate, and it provides no added meaning for the parameter.

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?

States a specific verb and resource ('every employee on the payroll master data, with today's contract') and immediately distinguishes scope (accountant role, personal data, not a plain member read). It also names a differentiating sibling, the single-employee GET for children/contract history, so an agent can route without opening a schema.

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?

Gives clear context and prerequisites: 'filter on status/employment_end yourself — no server-side filter, no paging' and 'read readiness before creating a payroll run', plus a pointer to GET …/employees/{employee_id} for children and contract history. It stops short of naming sibling list tools to use instead, but the when-to-use conditions are explicit.

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