withings_get_sleep_summary

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

With no annotations, the description carries the full burden. It adds useful behavior: default range of 7 days, typical data sources, and summary-level granularity. However, it does not explicitly state that the operation is read-only, whether it can be called with no parameters, or what happens when no data exists. These are clear gaps for an unannotated tool.

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?

Three short sentences with no filler. The purpose is front-loaded, followed by default behavior, source context, and a clear pointer to the sibling. Every sentence earns its place.

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 simple read-style tool with fully documented parameters, the description covers the primary use case, default range, sources, and the main alternative. It is slightly incomplete in that it doesn't address response shape or edge cases, but the absence of annotations and output schema make those gaps minor rather than critical.

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 100%, so the schema already documents all four parameters. The description adds a small amount of context by mentioning the default 7-day range and default fields (score, stages, HR/RR), but these largely mirror the schema defaults. No significant semantic value beyond the schema is added.

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 opens with a specific verb and resource: 'Fetch per-night sleep summaries' followed by concrete data categories (score, stages, HR/RR stats, snoring). It clearly differentiates from the sibling withings_get_sleep by specifying 'per-night' and pointing to minute-level detail as the sibling's scope.

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 final sentence explicitly states when to use the alternative: 'For minute-level detail within a night, use withings_get_sleep.' It also gives default range context (last 7 days) and indicates this tool is for summaries, making the selection decision explicit.

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