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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds the non-obvious prerequisite that the target device must be authorized and online, plus the clarification that path resolves on the remote device rather than the MCP server — genuine context beyond the annotations.

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?

Three short clauses, front-loaded with the action and target, followed by parameter disambiguation and a sibling pointer. No filler and nothing repeated from the schema or annotations.

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?

With no output schema, the description implies entries are returned and that file_info drills into one. Combined with the online/authorized precondition and parameter clarification, it is adequate for a two-parameter read tool; only return-shape details (pagination, entry fields) are left unstated.

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 0%, so the description must carry both parameters. It explains device_id as a registered device and path as the directory path on that device (explicitly not on the MCP server), which resolves the main ambiguity an agent would face. It does not specify path format, separators, or relative-vs-absolute handling.

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?

Specific verb+resource ('List directory entries') with the target scope named ('on an authorized, online remote device'). It also distinguishes itself from the file_info sibling by directing the agent there for a single entry, so an agent can tell the two apart without opening either schema.

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?

States the operating precondition (device must be authorized and online) and routes to the alternative 'file_info' for inspecting a specific entry. It stops short of explicit when-not-to-use guidance or naming other alternatives like read_file or list_devices, but the context is clear.

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