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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered by structured data. The description adds one genuinely useful behavioral fact beyond that: an empty state yields compact nationwide counts, effectively defining the default/no-argument response. It says nothing about response size, ordering, or how counts relate to coverage gaps.

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 the outcome and followed by input formats; no filler. The line break mid-sentence and the vague phrase 'field coverage' are the only slight costs to structure.

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 one-optional-parameter read tool with an output schema already defining return shape, the description covers purpose, accepted input formats, and the empty-input default — enough to invoke correctly. It omits any mention of what 'field coverage' is measured against, which leaves the summary's semantics slightly open.

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 0% and the single 'state' parameter has no description of its own, so the description carries the full burden — and it does: accepted forms are abbreviation, name, or FIPS, and the empty string is documented as a valid value producing nationwide results. Only minor gaps remain, such as whether names are case-sensitive or partial matches are allowed.

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?

Uses a specific verb and resource: 'Get exact parcel record counts and field coverage', which tells an agent this is a coverage/count summarization tool rather than a record fetch like get_parcel or search_parcels. It stops short of naming or contrasting any sibling, so differentiation is inferred from the phrasing alone.

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 explicit when-to-use or when-not-to-use guidance relative to get_parcel, search_parcels, or list_datasets. The only usage signal is the implied 'call with empty state for nationwide counts', which is an input behavior rather than a routing rule.

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