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

Annotations already establish readOnly/idempotent/non-destructive/closed-world, so the bar is lower. The description usefully adds what the answer contains (official source links, state base rate when stated, date checked) and two explicit boundaries: not tax advice and no local tax coverage. It stops short of noting coverage limits or how ambiguous state guidance is handled.

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?

Three sentences, front-loaded with the core verdict, then answer contents, then the disclaimer. Every sentence carries information, though the middle sentence is dense enough that it could be trimmed slightly.

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?

There is no output schema, and the description compensates by enumerating what the response includes (verdict, source links, base rate, check date). Combined with the explicit boundaries and the fully-covered input schema, an agent has everything needed to call and interpret this correctly.

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 100%, so both parameters are already fully documented in the schema (including the DC allowance and the enum meanings). The description restates the state-level scope and audience categories without adding syntax or format detail beyond the schema, so baseline 3 applies.

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+resource+scope: whether state sales tax applies to residential/commercial cleaning in one US state or DC. The scope limit ('one US state or DC') is explicit, and it correctly frames itself as a state-level reference lookup, which no sibling tool overlaps.

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 usage through scoping (one state per query, home/commercial/both audience) but never states when to reach for this versus alternatives, nor any prerequisites or exclusions beyond 'does not cover local taxes'. Usage is inferable, not guided.

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