watershed_at

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

With no annotations, the description carries the full burden. It clearly states this is a read-only lookup ('Look up', 'Point-in-polygon query') and describes the exact input alternatives and return fields. It does not mention error conditions or rate limits, but for a simple lookup tool the disclosure is strong.

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 well-structured with a one-sentence summary, a concise mechanism explanation, then Args and Returns sections. Every part adds value without redundancy. The front-loaded summary quickly tells the agent what the tool does.

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 the full workflow: what the tool finds, which layer it queries, the geographic coverage, how to provide inputs, and what the return dict contains. Given the low parameter count and presence of an output schema, this is complete and ready for an agent to use.

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%, but the description fully compensates by explaining each parameter's role and the mutually exclusive relationship: 'Provide either ``address`` or both ``lat``/``lon``.' It also specifies address format with an example and clarifies that lat/lon are used only if address is not given.

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 opens with a specific verb phrase 'Look up the named watershed/basin containing a location' and identifies the exact data layer ('City of Charlotte "Watershed Basins" layer'). It clearly distinguishes this from sibling 'at' tools like area_plans_at or tree_canopy_at by naming the resource and the point-in-polygon mechanism.

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 gives explicit usage context: 'Provide either ``address`` or both ``lat``/``lon``.' It also states the geographic coverage ('covers all of Mecklenburg County'), which helps the agent decide if the tool is appropriate. It does not explicitly list alternative tools, but the context is sufficient.

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