etabs_set_modal_case

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

Annotations already declare the operation is a non-read-only, non-destructive, non-idempotent write, so the description does not contradict them. However, it adds no behavioral context beyond that: no statement about prerequisites (unlocked model, prior modal case definition), whether a re-run of analysis is required, or permission/state requirements — meaningful gaps for a settings mutation.

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, well-formed sentence with the action front-loaded and no filler — effectively sized for a simple setter. The terseness edges toward under-specification rather than waste, so it is efficient but not maximally informative.

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 values need not be described, and the tuning hint partially covers intent. Still, for a mutation that feeds seismic/eigen analysis, the description omits workflow context (interaction with mass source, response-spectrum scaling, and the need to re-run analysis), leaving an agent to infer the surrounding procedure.

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 must carry the parameter burden. It only loosely gestures at 'how many modes' and never explains the distinct roles of min_modes vs max_modes, the defaults (Modal/12/1), the 1-1000 bounds, or what 'case' names are acceptable.

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 (Set) and resource (the number of modes the eigen modal case computes), so an agent immediately knows what is being modified. It does not, however, name or contrast itself with any sibling (e.g. etabs_define_response_spectrum or etabs_set_mass_source), 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?

The parenthetical '(raise it until mass participation is enough)' gives a real usage criterion for tuning the value, which is more than nothing. But there is no explicit when-to-use/when-not-to-use guidance, no ordering constraint (must be set before running analysis), and no mention of alternatives for modal mass participation.

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