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

With no annotations provided, the description carries the full behavioral burden. It usefully discloses the US Census data source, the fact that a city/town name returns the centroid, and the US-only scope. It could add more detail about failure modes or coordinate ordering, but the core behavior is transparent enough for a single-parameter tool.

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, front-loaded with the core purpose, followed by concrete examples and usage context. Every sentence adds value, and there is no redundant or filler text.

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?

For a one-parameter tool with no output schema, the description covers accepted input forms, geographic scope, output type, and downstream usage context. Slight gaps remain around error handling and coordinate format, but these are not critical for an agent selecting and invoking the tool.

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?

The input schema covers the parameter at 100%, so the baseline is 3. The description adds meaningful semantic detail beyond the schema by explaining that a place name resolves to the city centroid and by reinforcing the two accepted input forms with examples. This extra context helps an agent understand what values are valid.

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 a specific verb ('Convert') and resource ('US street address OR city/town name') with a concrete output ('latitude/longitude coordinates'). It also distinguishes itself from sibling location-related tools (weather, elevation, earthquakes) by positioning geocode as the coordinate lookup step.

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 when-to-use guidance: 'Call this first whenever you have a location as text and need coordinates for the weather or elevation tools.' It also provides a clear exclusion with 'US locations only,' telling the agent when not to use it.

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