health_get_breathing_rate

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

With no annotations, the description carries the full burden and does disclose meaningful behavior: it reads from cache by default, auto-syncs if stale, and the live flag forces a re-fetch from the API before reading cache. It does not mention auth requirements or rate limits, so it stops short of a 5.

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?

Front-loads the one-line summary, then the illness-signal rationale, cache behavior, and a clean Args block. Well organized; the 'typical adult range' line is marginally extraneous but arguably aids interpretation of results.

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?

Although an output schema exists, the description still names the return shape (one entry per night with breaths_per_min and data_source), so an agent knows exactly what comes back. For a 3-param read tool with no annotations, coverage of purpose, params, cache behavior, and output is complete.

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 coverage is 0%, so the description must compensate entirely, and it does: all three parameters are documented with accepted date formats ('YYYY-MM-DD', 'YYYY-MM', '30d'), defaults for start_date/end_date, and the exact effect of live. Nothing about the params is left to inference.

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 (get nightly breathing rate, average breaths per minute during sleep) and pins the measurement context to sleep tracking, which distinguishes it from siblings like health_get_heart_rate, health_get_hrv and health_get_spo2 without needing to open any schema.

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?

Offers interpretive context ('useful as an illness/recovery signal', 2-3 bpm above baseline) but never states when to choose this tool over the other health_get_* siblings or under what conditions a call is warranted. Usage is implied rather than specified.

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