get_forecast

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

With no annotations, the description carries the behavioral burden. It discloses a critical non-obvious behavior: stages are on the gage's own datum and cannot be compared to surveyed elevations without the describe_location offset. This is valuable context beyond what the schema or annotations provide, though it stops short of describing output structure or pagination.

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 three sentences with the core purpose first, followed by the datum caveat and identifier types. Every sentence adds necessary information without redundancy or filler.

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 single-parameter tool with no output schema, the description covers the data source, datum semantics, accepted identifiers, and relationship to describe_location. It could be slightly stronger by indicating whether the result is a time series or single current values, but overall it is sufficient for tool selection and basic 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?

The schema only specifies 'identifier' as required string with no description. The description adds meaning by explaining it accepts either a USGS identifier or an NWS location id, which is essential for correct invocation. It doesn't provide format examples or constraints, but the clarification is significant.

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 the tool returns 'Observed and forecast stage from the NOAA National Water Prediction Service, with the flood thresholds that give them meaning.' This specific verb and resource, plus the mention of thresholds, distinguishes it from siblings like get_model_forecast or get_latest.

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 implies when to use the tool (when you need stage data on the gage's own datum) and references describe_location for surveyed elevation offsets, but it does not explicitly contrast this tool with get_model_forecast or other alternatives. No clear 'use this instead of X' guidance is provided.

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