query_heart_rate

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

With no annotations, the description carries the full burden of behavioral disclosure, but it provides none. It does not mention return format, pagination, filtering behavior, or whether it is read-only. The description simply restates the tool's name and offers no behavioral context.

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 extremely short, but this is under-specification, not conciseness. A tool with four parameters and no other context requires more than a single phrase to be useful. Every word is wasted because no additional meaning is conveyed.

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 tool's complexity (4 parameters, no output schema, no annotations) and the presence of sibling query tools, the description is woefully incomplete. It offers no return value information, parameter semantics, or usage context, making it impossible for an agent to correctly invoke or select the tool.

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 0%, so the description must compensate by explaining parameter meanings, but it does not. No parameter such as start_date, end_date, sample_type, or limit is mentioned, leaving the agent completely dependent on the schema's minimal field names.

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 'Query heart rate samples' clearly identifies the verb and resource, distinguishing it from related query tools like query_sleep or query_workouts. However, it does not explicitly differentiate itself from potentially overlapping tools like query_metric_series, so it is clear but not fully distinguished.

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?

No guidance is provided on when to use this tool versus alternatives. There are no exclusions, alternatives, or contextual hints. The only implied usage is that it queries heart rate data, which is not enough to guide selection among many similar query tools.

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