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 without the description. The description adds a useful input/output summary and notes a 'life-time recovered' computation, but never discloses the underlying model or assumptions behind that health estimate.

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?

Four short sentences, front-loaded with the core computation before inputs, outputs, and the cross-reference. Little waste, though the list_bundles pointer is marginally outside the tool's own scope.

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 simple deterministic calculator with full annotations and an output schema, the definition covers purpose, usage context, inputs, and return shape, so an agent can call it correctly. Only the health-savings model assumptions are left implicit.

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% and an output schema exists, so the baseline is 3. The description names two of the three parameters ('cigarettes/day, pack price') and omits cigarettes_per_pack (default 20), adding no format or unit detail beyond 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?

States a specific verb and resource: computing money and health-time saved by quitting smoking, with the key inputs and outputs named. Within a sibling set of ~350 calculators, 'smoking savings' (money + recovered life time) is unambiguous and cannot be confused with any sibling such as calculate_bac_points or calculate_led_savings.

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?

'Use for motivation and budgeting' supplies a context but no conditions, exclusions, or alternatives. The 'See list_bundles for related sante calculators' line is a discovery hint rather than routing guidance for this tool.

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