wan_status

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the read-only nature is covered. The description adds the important behavioral detail that it queries the router live on every call with no caching, which is not in annotations and affects expected latency and freshness. It also lists the specific metrics reported. No contradiction with 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?

Two sentences with zero waste. The first sentence states the core function and output; the second adds usage context and the sibling distinction. Every clause carries information, and the most important info (what it does) is front-loaded. Perfectly sized.

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?

Given there are no parameters and the output schema exists (per context signals), the description sufficiently covers what the tool does, when to use it, and what to expect. It also notes the live-query behavior, which is important for agents deciding between this and cached tools. Nothing an agent needs to call it correctly is missing.

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 schema is empty and there is nothing to describe. Per instructions, baseline for 0 params is 4. The description adds value by enumerating the output fields (per-uplink state, WAN IP, uptime, CPU, memory), which implicitly tells the agent what the call returns. It doesn't need to explain any input semantics.

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?

Description states a specific verb (Report) and resource (WAN connectivity and router health), enumerating concrete data points (uplink state, WAN IP, uptime, CPU, memory). It explicitly names the sibling tool list_devices and the condition that selects it, distinguishing the tool without ambiguity.

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?

Provides explicit when-to-use guidance: 'diagnose is the internet down?' or check the public IP. Clearly states what it is not for (LAN devices) and names the alternative (list_devices). This is exactly what the dimension asks for – both positive and negative use cases.

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