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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered structurally. The description adds the return shape, which is somewhat redundant given the output schema, and discloses no formula, edge-case behavior (e.g., surplus/deficit handling) or limits.

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?

Two short sentences, purpose front-loaded, with the return shape and a cross-reference appended. Nothing is padded, though the return-shape sentence carries little weight since an output schema exists.

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?

Annotations cover safety, the schema documents all parameters, and an output schema exists, so the description doesn't need to explain returns or parameters. For a simple three-input calculator it is 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 100% with all three parameters documented in EUR, so the schema does the heavy lifting. The description adds no additional meaning about how annual_rent, annual_charges and depreciation_annual combine, which is the baseline-3 case.

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 (Calculate) and resource (LMNP tax deficit) and even expands the acronym, so the agent knows the domain. It does not explicitly differentiate itself from the nearest sibling calculate_lmnp_amortization, but the deficit focus is distinct enough to identify the tool.

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 only guidance is 'See list_bundles for related immobilier calculators,' which is a discovery pointer, not a when-to-use statement. It never says when this applies versus calculate_lmnp_amortization, nor any prerequisites such as needing rent, charges and depreciation together.

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