Check Garmin China connection

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

Annotations already declare read-only, idempotent, and non-destructive behavior, so the description only needs to add context. It does so by introducing the 'cached' aspect and the 'minimal account status' return, which implies a lightweight payload. It doesn't detail network behavior or error handling, but with strong annotations coverage, this is acceptable.

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 a single, concise sentence (11 words) that front-loads the primary action and result. There is zero fluff or repetition—every word 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 tool with no parameters, a clear purpose, and an output schema (which covers return value expectations), the description is fully adequate. Combined with rich annotations, nothing is missing for an agent to invoke it correctly.

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?

The tool takes no parameters, and the schema is fully covered (0 properties). The description adds no parameter-specific info, which is unnecessary given the absence of parameters. Baseline for 0-parameter tools is 4, and the description meets this with no redundancy.

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 states the tool's function with a specific verb ('validate'), resource ('cached Garmin China authentication'), and outcome ('return minimal account status'). It is distinct from sibling tools that all fetch data, since this tool focuses on connection/auth status rather than specific metrics.

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 provides clear context—this tool checks authentication validity—which is enough for an agent to know when to call it (e.g., before making other API calls). It does not explicitly mention alternatives or exclusions, but given the simplicity of the tool and that no sibling serves a similar purpose, the usage intent is unambiguous. Slight deduction for not stating 'use when needing to verify connectivity' explicitly.

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