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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds two things annotations cannot: the ten-year lookback window on returned history and a hard cost of $0.25 USDC via x402, which materially affects whether an agent should call it. No error or coverage semantics are given beyond the US-only scope.

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 sentences, front-loaded with the resource and its payload, closing with use cases and cost. No filler and nothing an agent must scroll past to reach the key facts.

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 carries the return-value burden and does so by enumerating the specific fields returned. Combined with full parameter documentation, the US-only scope, and the price, an agent has everything needed to decide and call 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%: the address param carries a formatted example and the language param enumerates every code with a note that pricing is identical across languages. The description adds nothing about either parameter, so the schema baseline of 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?

Specific verb+resource ("Property transaction history for any US address") followed by an enumerated payload: sale date/price, prior transactions, price-per-square-foot trajectory, ownership chain, deed types, mortgages, current owner. This is clearly distinguishable from sibling enrichment tools like interzoid_building_profile or interzoid_address_parse.

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?

"For real estate research, valuation, and due diligence" gives concrete selection context, so an agent knows the class of task this serves. It stops short of explicit exclusions (e.g., when to prefer interzoid_building_profile or address parsing instead), so it lands at 4 rather than 5.

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