calculate_heart_rate_zones

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

With no annotations provided, the description carries the full burden. It indicates a computation of zones, which is inherently non-destructive and read-only. However, it does not disclose return format, potential constraints, or whether it modifies any state. For a calculator, behavior is fairly predictable, but more detail would improve transparency.

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 two sentences long, front-loaded with the primary purpose, and includes a reference to related tools with no extraneous information. Every sentence serves a purpose, making it highly concise and well-structured.

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 that an output schema exists (not shown but indicated by context signals), the description does not need to explain return values. It covers the core functionality, method options, and a pointer to related tools. While it could elaborate on zone definitions or formulas, it is sufficient for a calculator tool with an output schema.

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?

Input schema has 100% description coverage for both parameters, so the schema already explains max_hr and resting_hr. The description adds that resting_hr is for the Karvonen method, which is already clear from the schema description. Thus, the description provides little added value beyond the schema, meriting a baseline 3.

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 the tool calculates heart rate training zones Z1-Z5, optionally using the Karvonen method. It uses a specific verb ('calculate') and resource ('heart rate training zones'), and distinguishes itself from sibling calculators by mentioning a related tool 'list_bundles' for other 'sante' calculators.

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 description gives a hint about alternatives by referencing 'list_bundles' for related calculators, but it does not explicitly state when to use this tool versus others, nor does it specify prerequisites or when not to use it. The 'optionally' clause gives some usage context but lacks comprehensive guidance.

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