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

Annotations already declare read-only, idempotent, non-destructive behavior, and the description adds useful context beyond that: annual results, assumptions, provenance, a portable input artifact, and no saved-record lookup or mutation. This gives an agent a solid behavioral profile for invocation.

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?

The description is compact and front-loaded: the calculation and comparison come first, followed by access and return-value notes. Every sentence adds useful information without 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?

For a complex calculator with no output schema, the description explains what is returned and reinforces the absence of persistence or mutation. It could do more to surface the Canadian/provincial scope and required assumptions beyond what the title and schema carry.

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?

The input is a single deeply nested object, and schema description coverage is reported as 0%. The description gestures at 'the person’s supplied numbers' and an alternative, but does not explain required fields such as province, people, annualSpending, or assumptionsAccepted, leaving most parameter meaning to the 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 uses a specific verb-resource pair, 'calculate ... retirement', and explains the core comparison: whether savings cover spending plus one explicit alternative. It clearly distinguishes this as a first-plan calculation rather than a record lookup or mutation.

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 establishes the context clearly: use the person’s supplied numbers, it is free with no sign-in, and it does not perform saved-record lookup or mutation. There are no sibling tools to compare against, but the description stops short of explicit when-not-to-use guidance.

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