CGM Libre status

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

Annotations already declare readOnly, idempotent, and non-destructive behavior, so the description adds value by detailing what configuration is reported. It doesn't mention side effects or output format, but for a read-only status check this is sufficient beyond the annotation coverage.

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?

Two sentences with no wasted words. The first sentence lists the reported items, the second gives the usage context. It is front-loaded and efficient.

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 status/configuration tool, the description covers what it reports and when to use it. It lacks an explicit return format, but the lack of an output schema makes that less critical. It also gives a clear pre-call use case, which is helpful.

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 input schema already documents the single optional parameter (privacy_mode) with a clear enum and description, achieving 100% schema coverage. The description does not add any parameter-specific guidance beyond the schema, so the baseline of 3 is appropriate.

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 uses the specific verb 'reports' and enumerates the exact configuration items (region, credential presence, patient id pinning, live/mock mode). It also gives the purpose ('confirm the Libre path is wired'), which distinguishes it from generic status tools.

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?

It explicitly states when to use the tool: before calling glucose tools with CGM_PROVIDER=libre. It doesn't provide exclusions or name alternative siblings, but the use case is clear and actionable.

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