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

readOnlyHint=true already declares the safe read profile, so the bar is lower. The description reinforces this with 'Non-mutating computation' and adds the useful detail that the Engine API call is POST /rationale (relevant given the counterintuitive POST for a read). No disclosure of rate limits, auth, or return shape.

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 short sentences, zero waste, with the core purpose front-loaded before the mutability note and endpoint. Nothing extraneous.

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?

No output schema exists, yet the description does not indicate what the rationale response contains, and gives no usage context relative to siblings. For a computation tool with nested inputs, this leaves the agent with adequate but incomplete information.

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 83%, above the 80% threshold, so the schema already documents age, sex, evidence, and dev_mode. The description adds no parameter syntax or format detail beyond casually referencing 'the evidence'. Baseline 3 is appropriate.

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+resource: 'Explain WHY the diagnostic engine wants to ask its next question, given the evidence.' An agent can tell it computes a rationale for the next question. However, it does not explicitly differentiate itself from the similarly-named sibling infermedica_explain, so it falls 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?

The phrase 'given the evidence' implies that evidence must be supplied, but there is no explicit when-to-use guidance and no mention of alternatives such as infermedica_explain or infermedica_diagnosis. The agent must infer placement in the workflow.

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