signalgrid_device_identity

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds value by specifying exact return keys and the error behavior when system_profiler fails, which is behavioral context beyond what the annotations provide.

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 structured with a short title line, a sentence about usage context, and a clear return specification. It is concise and every sentence contributes either to purpose, usage, or return behavior, though the 'Returns' section duplicates what an output schema would typically provide.

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 no-parameter tool with an output schema and rich annotations, the description covers the tool's purpose, the semantic meaning of the identity, and error handling. It does not address explicit alternatives, but that's a usage guideline matter, and overall this is sufficient for a simple read-only tool.

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 has zero parameters, so the baseline is 4. The description correctly omits parameter details, and the schema has 100% coverage with no parameters to document.

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 the tool's function: providing hardware identity details (serial number, model, hardware UUID, chip, activation lock). The phrase 'stable anchor for a device trust record' adds context and distinguishes it from sibling system-info tools, though it lacks an explicit action verb like 'get' or 'list'.

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 implies usage context by positioning the data as a stable anchor across OS reinstalls, but it does not explicitly state when to use this tool over alternative siblings, nor does it mention any exclusions or alternatives. It provides a rationale for why to use it but no explicit comparison.

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