List Financial Years

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

Annotations already declare read-only, idempotent, non-destructive. The description adds value beyond annotations by stating the return contents (ID, date range, accounting method) and the critical fact that the ids are sequential, not calendar years. No contradiction.

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?

The description is front-loaded with purpose, immediately followed by a crucial warning, an illustrative example, structured args/returns, and no filler. Every sentence contributes necessary context.

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?

Given the tool's low complexity, one optional param, and no output schema, the description fully covers what the tool returns and why it's useful, including the ID mapping that prevents misuse. With annotations covering safety, this is 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?

Schema coverage is 100% and the parameter has a clear enum/default/description. The description repeats the parameter information without adding any new semantics, so it stays at the baseline of 3.

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?

The description states a specific verb and resource: 'List all financial years configured in Fortnox.' It distinguishes from sibling tools by clarifying this tool provides the sequential ID mapping needed by voucher tools, not just a generic list.

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?

Explicit guidance is given: 'Use this tool first to find the correct ID' for voucher tools, with a concrete example mapping ID 4 to a calendar year. This clearly tells when to use this tool in relation to alternatives like fortnox_list_vouchers.

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