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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety and idempotency are covered. The description adds useful domain behavior ('including duration abatements') that the annotations cannot express, but says nothing about assumption limits (e.g. that this covers secondary residences only, or what regime/rates are applied).

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?

Four short sentences, front-loaded with the purpose before inputs and outputs. The 'See list_bundles for related finance-france calculators' line is the weakest element but is a brief, potentially useful navigation hint.

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?

An output schema exists, so the 'Returns tax due, social charges, net gain' sentence is redundant rather than necessary. Given full annotation coverage, 100% schema coverage and 3 simple scalar parameters, the description supplies enough context for correct invocation aside from the phantom 'work cost' parameter.

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%, so the baseline would be 3, but the description actively misleads: it lists 'work cost' as an input while the schema defines only purchase_price, sale_price and years_held with additionalProperties=false. An agent following the description would pass a parameter that gets rejected.

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 with domain precision: 'Compute French property capital gains tax (plus-value immobilière) including duration abatements.' This is far more informative than the title. However, it does not distinguish itself from the near-identical sibling calculate_property_capital_gains_fr, leaving the agent unable to tell which one to pick.

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 line 'Use for sellers of secondary residence' gives a clear usage context, which is better than nothing. But with a near-duplicate sibling (calculate_property_capital_gains_fr) in a 300+ tool set, the absence of any 'use this instead of X' or exclusion guidance is a real routing gap.

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