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

No annotations are provided, so the description carries full burden. It states 'Returns rent ratio % and verdict', which is transparent about outputs. For a simple calculation with no side effects, this is sufficient, though it could mention that no data is stored or modified.

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 sentences: purpose, usage, parameters+output+sibling reference. No waste. Every sentence adds value.

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 simple nature of the tool, the description covers purpose, inputs, output, and related tools. It doesn't detail verdict criteria or edge cases, but the presence of an output schema likely fills gaps.

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% with clear descriptions ('Monthly rent', 'Monthly income'). The description adds 'gross' for income but otherwise repeats schema. Baseline 3 is appropriate as description adds little beyond schema.

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 clearly states 'Compute the rent-to-income ratio' with a specific verb and resource. It distinguishes from siblings by mentioning 'see list_bundles for related immobilier calculators', and the rule of thumb adds context.

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?

It explicitly says 'Use to assess housing affordability' and gives a rule of thumb, providing clear usage context. It also hints at alternatives via list_bundles, but does not explicitly state when not to use.

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