garmin_briefing

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

The description adds substantial behavioral detail beyond the readOnlyHint/openWorldHint annotations: sections are fetched concurrently, partial failures surface in 'sectionsUnavailable' instead of failing the whole call, and unsupported device metrics return their own note. It also clarifies the output is numeric only and gives interpretation guidance. This is exactly the kind of contextual behavior an agent needs.

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 tightly written, front-loaded with the purpose, and each subsequent sentence adds meaningful behavioral or interpretive detail. There is no filler or repetition, and the formatting with line breaks aids readability.

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?

The description fully covers what the tool returns, how failures are handled, and the distinction from per-metric tools. An output schema exists, so return structure doesn't need elaboration. The only notable gap is the lack of any detail about the date parameter's semantics, which prevents this from being fully 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?

There is exactly one parameter, 'date', but the description says nothing about it. The input schema only shows it is an optional string or null with a default of null. With 0% schema description coverage, the description needed to at least imply the date format or default behavior; it does not, leaving the agent to guess.

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 clearly identifies a specific aggregate snapshot tool ('Morning snapshot in one call') and names the exact metrics included: sleep, HRV, Body Battery, readiness, stress, and RHR. It distinguishes itself from the many individual sibling metric tools by emphasizing the one-call aggregation benefit.

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 description strongly implies when to use it: when answering 'how am I doing today?' with a broad morning snapshot, rather than calling six separate metric tools. It also warns that it returns numbers only and no training advice, which is useful routing guidance. However, it never explicitly names sibling tools or states when NOT to use it in favor of a single metric tool.

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