list_zones

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

Without annotations, the description carries the full burden of behavioral disclosure, and it makes a genuine attempt: 'every' implies no pagination, and the parenthetical enumerates the return fields. However, it omits how the optional device parameter interacts with the scoping phrase 'on a controller'—must one device be specified, or does it default to all? It also doesn't disclose error behavior or whether the list is sorted. Adequate for a simple read operation, but not rich in caveats.

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 a clear verb first. The parenthetical efficiently conveys the output fields without embedding them awkwardly in the prose. No wasted words; every token contributes meaning.

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 presence of a separate output schema (noted in context signals) means the description doesn't need to specify return types, and it wisely uses the parenthetical to name the fields (number, name, enabled state) that any agent would need to know they can expect. The single optional `device` parameter is its only real complexity, and while the description hints at its purpose ('on a controller'), it could add a brief note on what omitting it does (e.g., default to all controllers) without bloating the text. For a tool this simple, this is close to as complete as it needs to be.

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%, meaning the JSON Schema offers only the parameter's name ('device'), type (string/null), and default (null) with no free-text explanation. The description's word 'controller' provides the sole semantic bridge connecting the `device` parameter to the conceptual domain of zones, hinting that this is likely the controller identifier to query. Yet the description never explicitly names `device` or explains what happens if it's null, so the compensation is partial.

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 uses a specific verb ('List') plus a concrete resource ('every zone on a controller') and includes a parenthetical specifying the returned fields (number, name, enabled state). This makes it immediately distinguishable from siblings like list_devices and list_schedules, which follow a similar naming pattern but operate on different resources. The word 'every' reinforces the exhaustive scope 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?

Usage is implied: an agent can infer this is the right tool when it needs zone information, especially before starting zones via start_zone or start_zones. However, there's no explicit statement of when NOT to use it or which alternative to choose (e.g., no 'for device inventory use list_devices'). The description provides the 'what' but not the conditional 'when/why' that separates a 4 from a 5.

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