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

Annotations already mark the tool read-only and non-destructive; the description adds important behavioral context: it cites sources, never fabricates fees/thresholds, and falls back to 'I don't have that on file'. This explains grounding and failure behavior beyond the structured hints.

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 are front-loaded with purpose, then behavior, then usage examples. Every sentence contributes; there is no filler or repetition.

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?

The description covers scope, data sources, return style, fallback behavior, and example uses. With an output schema present and annotations covering safety, nothing essential is missing for an agent to invoke the tool 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 coverage is 100% and the description adds only example phrasing for the question and address parameters, not new format or constraints. Baseline 3 is appropriate because the schema carries the parameter documentation.

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?

The description names a specific resource and action: grounded permit Q&A for a Seattle-area address, with a return value ('cited answer'). It is distinct from sibling tools like check_permit_requirements or get_neighbor_permit_activity because it combines parcel lookup, jurisdiction rules, neighbor activity, and municipal code into an answer.

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?

It explicitly says 'Use for natural-language permit questions' and gives two concrete examples, so an agent knows when to invoke it. It does not mention exclusions or route to alternatives, so it stops short of a full 5.

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