Get Real-Time Water Data

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

Annotations already indicate read-only and idempotent behavior, and the description adds valuable context: data is updated every 15 minutes and covers rivers, streams, lakes, and reservoirs across the US. No contradictions.

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?

Two sentences efficiently convey purpose, scope, update frequency, and prerequisite. No fluff 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?

Given the tool's moderate complexity (3 parameters, output schema present), the description adequately covers data type, update frequency, geographic scope, and how to obtain the required site number. No gaps.

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?

Input schema covers all parameters with descriptions (100% coverage). The description adds context for 'site_no' by mentioning water.sites, but doesn't detail parameter usage beyond that. Baseline score of 3 is appropriate as description adds marginal value.

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 that it retrieves real-time streamflow, gage height, water temperature, and conductance for a USGS monitoring site. It also distinguishes itself from the sibling tool 'water.usgs.sites' by focusing on real-time data retrieval versus site discovery.

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 provides clear context for when to use this tool (getting real-time data) and explicitly references the prerequisite tool 'water.sites' to find site numbers. It lacks explicit when-not or alternative tools but is otherwise helpful.

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