discover_lights

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds the useful context that discovery happens over UDP broadcast (implying local-network adjacency and possible timeouts), but it does not say how long the scan takes, whether it blocks, or what it returns.

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?

A single front-loaded sentence with no filler; the verb, resource, and mechanism all appear in the first few words. Nothing could be trimmed without losing information.

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 zero-parameter read-only tool this is nearly complete, and the UDP/local-network wording conveys the key constraint. The remaining gap is that with no output schema, the description never indicates that it returns a set of discovered bulbs (and whether that set can be empty).

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 takes zero parameters, so per the rubric the baseline is 4. There is no parameter semantics to add, and the description correctly implies a no-argument operation.

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?

States a specific verb (Scan), a specific resource (WiZ smart bulbs), and the mechanism (UDP broadcast on the local network). This implicitly and clearly distinguishes it from the sibling list_lights, which enumerates already-known bulbs rather than discovering them.

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 the when-to-use case (finding bulbs on the network) but never states it explicitly, nor does it name list_lights as the alternative for already-known bulbs. Usage is inferable but not spelled out.

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