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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds value by enumerating the data categories returned and noting the compact default is tuned for AI context. It doesn't contradict annotations and provides useful behavioral context beyond the structured fields.

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 pack a clear verb, resource, scope, usage examples, and an alternative. Every word earns its place, with no fluff or repetition.

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 get-by-id tool with strong annotations and a schema explaining compact, the description covers what data it returns, when to use it, and why it's preferable. No output schema is present, but the description lists key return categories, making it sufficiently complete for an agent to invoke confidently.

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 coverage is 50%: compact is well-described, printer_id only has type. The description says 'by id' which clarifies printer_id's role, and 'Cheaper and less noisy' reinforces why compact defaults to true. However, it doesn't add new meaning for printer_id beyond what the schema implies, leaving that parameter semantically thin.

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 gets details, status, temps, current job, filament, and notifications for one specific printer by id. It explicitly distinguishes itself from list_printers, making its purpose unambiguous.

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 gives explicit when-to-use guidance: whenever the user asks about a single printer they've already identified, with concrete examples. It also names the alternative (list_printers) and explains why this tool is preferred (cheaper, less noisy).

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