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

Annotations declare a write operation (readOnlyHint=false) that is non-idempotent and non-destructive. The description adds real business context beyond that: a 24-hour-per-day validation cap, the immediate-attestation workflow via approve=true versus a pending state, and the payroll scope. It stops short of covering auth requirements or duplicate/error behavior.

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?

A single dense paragraph that front-loads the action, then the behavioral rules (24h cap, approve), then the argument list. Every clause carries information; the trailing argument list is a bit list-like but still earns its place given 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 an 8-parameter write tool with no output schema, the description covers the action, a validation rule, the approval workflow, and all parameter formats. It omits error/duplicate handling and where employee_id originates, but is otherwise complete enough to invoke correctly.

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 only 13%, so the description must compensate, and it does: it lists all eight arguments, adds the work_date format (YYYY-MM-DD), an example for hours (7.5), and enumerates the kind values (arbete|overtid|ob|sjuk|semester|vab|ledig) that appear nowhere as schema enums. It does not explain employee_id or project sourcing beyond a brief gloss.

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: add a time entry for an employee (e.g. from a time slip). This clearly distinguishes it from list_time_entries, delete_time_entry and review_time_entries, though it does not name those siblings explicitly.

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?

Provides an era-of-use hint ('t.ex. från en tidlapp') and explains the approve=true vs pending-attestation behavior, which effectively guides the caller. However, it names no alternatives and gives no explicit when-not-to-use guidance, so usage is implied rather than spelled out.

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