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

With no annotations, the description carries the full burden of behavioral disclosure. It thoroughly describes what data will be returned, including the conditional inclusion of CMHC housing starts and StatCan New Housing Price Index for covered metro areas. It also discloses data sources and that each block lists its sources, providing transparency about the tool's data provenance.

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?

The description is two sentences, front-loaded with the core purpose and metric list, followed by conditional details and source attribution. Every sentence adds value, with no wasted words, making it highly efficient.

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?

Despite having no output schema, the description enumerates all key return metrics (reference price, yoy change, sales volume, months of inventory, days on market, 5-year growth) and explains the conditional extra data. It also clarifies the geographic scope and data sources, providing a complete picture 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% for the single 'ville' parameter, providing examples. The description adds meaningful context by specifying the tool is for Canadian cities and that metro-area coverage affects additional outputs, which goes beyond the schema's basic description.

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 clearly states the tool's purpose: retrieving current housing-market statistics for a Canadian city, listing specific metrics (reference price, yoy change, sales volume, inventory, days on market, 5-year growth). It distinguishes itself from sibling tools by focusing on market data rather than buying/renting advice, rates, taxes, or expert contact.

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 description explicitly says 'Call this for current housing-market figures' which provides clear context for when to use it. However, it does not explicitly state when not to use it or name alternative tools for other types of queries, though the specificity implies alternatives exist for other purposes.

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