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

Annotations already declare readOnly/idempotent/non-destructive, so the safety bar is low; the description adds real value by specifying the calculation content (skatt + arbetsgivaravgift) and the non-posting behavior that matches readOnlyHint. It does not describe output format or the effect on subsequent run_payroll, keeping it below 5.

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 before the dense argument list, and every clause (types, formats, enum values, sign conventions) earns its place given the sparse schema. The parameter enumeration is run-on but justified by the low schema coverage.

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 6-param, low-schema-coverage tool with no output schema, the description is thorough on inputs and behavior. It stops short of explaining return values or how the result feeds run_payroll, which is the main remaining gap.

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?

With only 17% schema coverage, the description carries the load and does so well: it documents orgnr, year, month, pay_date (YYYY-MM-DD format), and the full nested entries shape (employee_id, gross_cash_ore, benefit_ore, extra_tax_ore, components). It uniquely supplies the kind enum (LON|SEMESTER|OVERTID|...) absent from the schema and explains extra_tax_ore sign semantics (+extra skatt / −jämkning).

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+resource ('Förhandsberäkna en lönekörning') and the exact scope (skatt + arbetsgivaravgift), and the crucial negation 'UTAN att bokföra' separates it from the booking sibling run_payroll. An agent can distinguish this preview-calculation tool from run_payroll without opening either 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?

'UTAN att bokföra' clearly signals the preview-only context (use this to compute, not to post), which distinguishes it from run_payroll. However, no alternative sibling is named explicitly and there is no explicit when/when-not statement, so 4 rather than 5.

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