disk_list

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

readOnlyHint=true already tells the agent this is a safe read, so the '[READ]' prefix is largely redundant. The description does add useful context that target resolves against a named config entry and falls back to a default, but says nothing about pagination, scope of enumeration, or failure modes when a target is unreachable.

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 plus a parameter line, front-loaded with the action and its output fields. The '[READ]' tag and 'Args:' framing are mild overhead but nothing is padded or buried.

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 read-only, no-required-parameter list tool with no output schema, the description covers what the caller needs: what is listed, what comes back, and how the optional target resolves. Missing only edge-case behavior such as empty results or invalid target handling.

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 coverage is 0% – the single target parameter has no description in the schema – so the description must carry the load, and it does by explaining that the value is a TrueNAS target name from config and that omission selects the default. That is real added meaning, though it doesn't specify format or valid values.

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 and resource ('List physical disks') and enumerates the returned fields (name, serial, model, size, pool), which makes it easy to tell apart from pool_list or dataset_list. It stops short of naming a sibling to disambiguate against, so 4 rather than 5.

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 use case (inventory physical disks) and gives one concrete operating rule – omit target to use the default – but never states when to prefer this over pool_list, pool_get, or smart_test_results. Usage is inferable rather than explicit.

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