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

Annotations already cover read-only scope, and the description adds substantial beyond-schema context: uneven source coverage, that other municipal sources return lookup resources instead, that source update times may reflect bulk republishes, and that the attributions array and disclaimer must be passed through. This is exactly the kind of non-obvious behavior an agent needs.

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 purpose and source scope before the cautions, and most sentences carry real information. The attributions/disclaimer sentence is legally dense but operational, since it tells the agent to pass content through.

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?

An output schema exists, so return-value explanation is correctly omitted, and the description still flags the attributions/disclaimer elements the agent must forward. The remaining gap is the undocumented limit/city parameters, which is minor given the schema's defaults and constraints.

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 0%, so the description must compensate, and it does explain the critical address vs. county+parcelId requirement plus the exact match rules (recorded street/unit/ZIP). It says nothing about city, limit (default 20, max 50), or the zipCode pattern, leaving half the parameters unexplained.

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?

Names a specific verb and resource ('Read dated building-permit records for one exact property') and enumerates the payload fields and covered sources. It is unambiguous on its own, but it never contrasts itself with close siblings like wa_property_changes or wa_sale_history, so an agent must infer the boundary.

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?

'Use address or county plus parcelId' gives input-mode guidance and the description warns about incomplete coverage and that 'no records does not prove no permits'. However, there is no explicit statement of when to prefer this over wa_property_changes or wa_sale_history, which is the main selection risk.

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