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

Goes well beyond the annotations by disclosing three concrete behaviors: it locks every month of the year, it makes the INK2 and annual report drafts visible in the app, and it raises an error listing what remains when a step is incomplete. It also declares the required OAuth scope ('Scope book'), which annotations do not cover.

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 the action and its precondition, and every sentence carries information (precondition, effect, error behavior, scope, args). Slightly dense with parenthetical asides, but no significant padding.

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 2-parameter mutation tool with no output schema, the description supplies preconditions, side effects, error behavior and the required scope, which is largely sufficient. The main gap is the unspecified year parameter semantics.

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 coverage is only 50%: orgnr is well documented in the schema but year has no description, and the description merely names the arguments ('Argument: orgnr, year') without adding format, range, or which fiscal year is valid. It fails to compensate for the undocumented year 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 (Lås/lock the entire fiscal year) plus the precondition (the four year-end items are booked/skipped) and the resulting side effects. An agent can separate this lock operation from siblings like book_year_end_step or unlock_fiscal_year without opening the 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?

Clearly states when to use it: only once the four year-end items are complete (booked/skipped), and notes it corresponds to the 'Lås perioden' button in Årsbokslut. It does not explicitly name the inverse alternative (unlock_fiscal_year) or warn about when not to use it, so it stops short of full routing guidance.

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