get_spo2_data

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered, but the description adds nothing about behavior — it only describes a value coercion. It also does not disclose what data is fetched, for what date range, or in what form, leaving the behavioral picture empty.

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?

It is a single short phrase, so there is no bloat, but the content is misplaced and uninformative — brevity achieved by saying the wrong thing. Under-specification, not conciseness.

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 read tool that fetches a health metric, the description omits the metric, the date semantics beyond the schema, and any routing against sibling health-data tools. With no output schema, the description should carry this burden and does not.

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 100% and the sole `cdate` parameter is fully documented in the schema, so the baseline would be 3. However, the description introduces the name `lastSevenDaysAvgSpO2`, which is not a parameter at all, actively confusing rather than clarifying the input.

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 never states that the tool retrieves SpO2 data. Instead it describes an internal coercion of a string `lastSevenDaysAvgSpO2` to a number, which is an implementation detail rather than the tool's purpose. An agent reading this cannot tell what resource the tool returns.

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?

There is no guidance on when to use this tool, no prerequisites, and no mention of the many sibling data-retrieval tools (get_respiration_data, get_hrv_data, get_heart_rates) it must be distinguished from. Nothing helps the agent decide to call it.

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