List devices

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

The description explicitly states 'Read only', consistent with annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false). It adds value by describing the return structure, including fields like temperature_c and vibration_mm_s.

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 two sentences, front-loaded with purpose, and includes the return structure. Every sentence adds value with no wasted words.

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 explicitly lists the return schema fields, which is sufficient even though an output schema exists. It covers all necessary aspects for a simple list 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?

Schema description coverage is 100%, and the parameter (response_format) is well-documented in the schema with enum values and default. The description does not add extra meaning beyond the schema, so baseline 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 clearly states 'List every simulated machine with its latest reading and state', providing a specific verb and resource. It distinguishes itself from sibling tools by positioning itself as the initial discovery tool for device IDs.

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 explicitly says 'Read only. Use this first to discover valid device ids for the other tools', providing clear guidance on when and how to use this tool relative to its siblings.

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