calculate_rental_yield

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

With no annotations, the description carries the full burden, and it does disclose the computational scope: it accounts for service charges, vacancy allowance, maintenance, and produces a 5-year cashflow projection in addition to gross/net yields. It does not discuss assumptions or edge cases (e.g., how defaults interact), but for a stateless calculator the behavior is well communicated.

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?

A single, front-loaded sentence that states the computation before listing the inputs it accounts for. Every clause earns its place; there is no filler or repetition.

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?

There is no output schema, so the description usefully names the returns (gross and net yield percentages plus a 5-year cashflow projection). With 7 params fully covered by the schema and no annotations to compensate for, this is nearly complete; only assumption or edge-case detail is missing.

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%, so all seven parameters including defaults are already documented in the schema. The description echoes the same concepts (service charges AED/sq.ft, vacancy, maintenance) without adding format, range, or unit nuance beyond what the schema provides, so the baseline 3 applies.

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 gives a specific verb and resource: 'Calculates Dubai gross and net rental yield percentages,' and enumerates the cost components it factors in. It is clearly distinct in domain from the other calculators (fees, mortgage eligibility), but it never names or contrasts those siblings explicitly, so it falls just short of a 5.

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?

There is no statement of when to use this tool versus calculate_dubai_fees, calculate_mortgage_eligibility, or get_dld_area_analytics, and no prerequisites or exclusions. The only usage signal is implied by the subject matter (Dubai property investment analysis), which is weak guidance.

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