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

With no annotations, the description carries the full behavioral burden. It usefully discloses accuracy limitations ('Educational estimate; commune surcharges and value-enhancing-improvement deductions are not modeled'), which is valuable context, but it says nothing about output form, precision, or computational assumptions beyond those exclusions.

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?

Three tight sentences: purpose first, then coverage/capabilities, then caveats. No filler, and the most important context (scope and limitations) is front-loaded.

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-parameter calculator with no output schema and no annotations, the description covers purpose, cantonal scope, key mechanics, and modeling limits well. It could say more about the deferral mechanics or the return shape, but it is largely sufficient to call the tool 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 coverage is only 50%, so the description must compensate. It adds meaning for years_held (holding-period adjustments) and the ersatzbeschaffung fields (replacement-residence deferral), but sale_price, purchase_price, and the interaction between sale/purchase price and tax base are left to inference.

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 ('Estimate') and a precise resource ('Swiss cantonal real-estate capital gains tax/Grundstueckgewinnsteuer for a property sale'), including scope (all 26 cantons). It is clearly distinguishable from the portfolio/FIRE siblings like rebalance_portfolio and project_wealth_plan.

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?

The description implies context by noting it is an 'Educational estimate' for a property sale and covering holding-period and Ersatzbeschaffung scenarios, but it gives no explicit when-to-use/when-not guidance or named alternatives. Usage is inferable but not stated.

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