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

The annotations already establish the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the bar is lower. The description still adds meaningful behavior: it discloses that output is a categorization of states under a single topic, and decodes what each category actually represents (e.g., transfer-tax = states with no transfer tax, foreclosure = judicial vs non-judicial). It stops short of describing grouping/order of the returned state lists.

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?

Front-loaded with the jurisdiction, then a single dense sentence enumerating topics and their meanings, then a one-line usage cue. Minimal waste; the parenthetical glosses on each enum value are the only slight repetition against the schema, but they carry new information rather than restating enum strings.

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?

One enum parameter, no output schema, and strong annotation coverage — the description is nearly complete for this tool because it defines every topic option and the question type it answers. The only missing piece is any hint about the response shape (e.g., one list of states per side of the classification), which is minor given the absence of an output schema.

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 enum itself lists the five topics, so baseline would be 3. The description goes beyond the schema by explaining the semantic meaning of each enum value — exactly what the enum names alone do not convey — which is genuine added value over the raw parameter definition.

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 (lists) and resource (the states in each category for one topic), and front-loads the jurisdiction (UNITED STATES) which cleanly separates it from the sibling compare_states_au, compare_states_in, and compare_nations_uk tools. An agent can tell what it returns and for which country without opening the schema.

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 closing 'Use for "which states…" questions' gives a clear when-to-use cue tied to a recognizable question shape. It does not, however, mention the per-topic sibling deep dives (transfer_tax_us, attorney_at_closing_us, foreclosure_us, seller_disclosure_us, community_property_us), so the agent gets context but no explicit routing between this cross-state comparison and those single-topic tools.

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