get_stream_flow

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

No annotations are provided, so the description carries the full burden. It discloses that the data is live from the NWIS Instantaneous Values service and provides the site number format. It stops short of explicitly stating the operation is read-only or describing error cases, but for a single-param get tool this is adequate context.

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 concise sentences. The first front-loads the purpose and the data fields; the second covers site number format and how to find sites. No fluff or redundancy.

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?

There is no output schema, so the description should explain what is returned. It lists the three variables but not units or response format. The site-discovery URL and the service name give useful context, making it reasonably complete for a tool with one parameter.

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 100% for the sole parameter, so the baseline is 3. The description adds value by specifying the site number is 8-15 digits, giving a concrete example, and pointing to a site-discovery resource — all beyond the schema's generic 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 states a specific verb ('Get') and resource ('live stream flow') and explicitly lists the measurements (discharge, gage height, water temperature). This clearly distinguishes it from sibling tools focused on water quality and basin health.

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?

Usage context is implied by the description — it is for retrieving stream flow data — but there is no explicit guidance on when to use this tool versus the siblings, nor any 'when-not' conditions. The site-inventory URL is operational context, not tool-selection guidance.

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