plc_list_hardware

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuine context beyond that: results come from 'exact local profiles' rather than a live device, and coverage is partial, which materially affects trust in the output. It does not describe ordering, pagination behavior, or what 'partial coverage' omits, so it is useful but incomplete.

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 short sentences, front-loaded with what is listed before the caveat. Nothing is wasted, though 'using exact local profiles' is compressed to the point of ambiguity about what a 'profile' is.

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?

An output schema exists, so return-value explanation is not needed, and the safety annotations are rich. However, for a four-parameter paginated listing tool with two undocumented parameters and an unclear transaction model, the description does not do enough; the important accuracy caveat is present but parameter-level completeness is not.

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 50%: limit and offset are documented in the schema, while project_id and transaction_id carry no description anywhere. The tool description adds no parameter meaning at all, leaving the required project_id and the transaction_id semantics (unclear whether this participates in the begin/commit transaction workflow) entirely undocumented.

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 gives a specific verb ('List') and a specific resource ('configured NX, built-in and EtherCAT modules'), which is enough to distinguish it from siblings like plc_list_io or plc_list_ports that target different resource types. It stops short of naming any sibling, so the differentiation is inferred from the resource noun rather than stated.

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?

There is no statement of when to prefer this tool, when not to, or what alternative to use for related questions about I/O or ports. The one contextual sentence ('Configuration is not physical verification; coverage remains partial') warns about result reliability but does not route the agent between tools.

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