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

Annotations already establish read-only, idempotent, non-destructive behavior, so the safety profile is covered. The description usefully discloses that this is a pure computation combining a fixed $130 service fee with the state's government filing fee, and that it returns approval time and recurring annual cost — output content the annotations cannot convey. It does not say how current or sourced the fee data is, which matters for a pricing tool.

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?

The lead question and imperative answer are front-loaded, followed by the concrete output breakdown and example queries. The example list is somewhat redundant with the preceding sentence, but every part is relevant and the phrasing is tight.

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?

With no output schema, the description correctly carries the burden of explaining return values — total cost, approval time, and annual maintenance — which it does explicitly. For a one-parameter read-only calculator this is close to sufficient; only fee freshness and any non-resident surcharge caveats are unaddressed.

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 100% and the single parameter already documents both state-name and 2-letter-code forms. The description adds only light context — that any US state is accepted and that non-resident scenarios apply — which is marginal beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 states a specific resource and output: total cost to form a US LLC, broken down into a $130 service fee, state filing fee, approval time, and annual upkeep. It is immediately clear what calling it yields. It stops short of naming the sibling compare_llc_states, so an agent handling a multi-state comparison question gets no explicit differentiation.

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 context is concrete, reinforced with three representative phrasings including 'for a non-resident'. It gives no when-not guidance, such as directing multi-state comparisons to compare_llc_states or ongoing compliance questions to compliance_deadlines, so boundary cases remain inferential.

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