hw_module

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that this is a lookup keyed by ModuleIdent returning PDOs, CoE objects and diagnosis messages, plus the device-resolution rule, but says nothing about ambiguity handling or rate limits beyond that.

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, front-loaded with the resource and key, so the important information comes first. However, the parenthetical jargon and the run-on second clause about device resolution make it harder to parse than it needs to be.

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 lookup with an output schema present (so return values need no elaboration), the description is adequate on ident and device but silent on `revision` and on behavior when multiple modules match. Complete enough to invoke, but with visible gaps.

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%, so the description carries the burden. It explains `ident` (the ModuleIdent as hw_lookup's slots give it) and gives a detailed resolution rule for `device`, but `revision` goes entirely unexplained, leaving one of three parameters 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 names the resource (a module of a modular device, e.g. AX8000/EP/EL) and the identifying key (ModuleIdent), plus what it returns (PDOs, CoE objects, diagnosis messages). This is specific, but the verb is implicit ('is a module') and the phrasing is dense jargon rather than a clean action statement, so it falls short of a 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?

It gives a conditional rule for the optional `device` parameter (device's own file, then the paired module file by name, then the only one), which is genuine usage context. However, it never says when to prefer this tool over hw_lookup/hw_object/hw_diag or what happens if ident is unmatched, so guidance is implied rather than explicit.

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