get_heart_rate

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

No annotations are provided, so the description carries the full burden. It does disclose genuinely useful behavior — local-timezone ISO timestamps, bucket averaging, and bucket_minutes=0 meaning raw — but says nothing about permissions, data volume, rate limits, or pagination.

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?

Two telegraphic sentences with zero filler, front-loading the resource and its range scoping. Slightly under-specified rather than bloated.

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?

An output schema exists, so return values need not be described. However, for a 3-parameter tool with 0% schema coverage and no annotations, the description leaves meaningful gaps in parameter semantics and usage routing.

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. It explains bucket_minutes (=0 for raw, with a default of 5 implied by the schema) and clarifies timezone handling for the timestamps, but leaves start_iso/end_iso inclusive/exclusive semantics and format details unstated.

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: raw HR samples over a timestamp range, with bucketing behavior. It distinguishes itself from aggregation-oriented siblings like get_daily, though it never names them explicitly.

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 when-to-use guidance, no mention of prerequisites, and no routing to alternatives such as get_daily for aggregated views. The agent must infer that 'raw' implies low-level granularity.

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