Get ERCOT RT−DA spread forecast

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It adds valuable context: the forecast is issued before delivery and never revised, indicating a stable, non-mutating read operation. However, it does not explicitly state whether the tool is read-only, but that is implied by its nature.

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 two sentences, densely packed with essential information (provider, market, metric, forecast percentiles, immutability, and alternative tool). No wasted words, and the structure flows logically from definition to filter to alternative.

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?

No output schema exists, so the description should clarify return values; it mentions p10/p50/p90, which conveys the key output fields. Parameters are fully documented in the schema, and the alternative tool is named. It lacks an explicit response structure but is adequate for a forecast query 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?

Schema coverage is 100%, so the baseline is 3. The description adds semantic value beyond the schema by providing concrete examples for node_id (HB_BUSAVG, HB_NORTH) and explaining the spread definition, which helps interpret the filter's purpose.

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 the tool provides a live ERCOT day-ahead RT−DA price spread forecast with p10/p50/p90 percentiles, and defines spread = RT − DA. It explicitly distinguishes itself from get_forecast_track_record by noting that tool is for scored historical performance.

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 explicitly directs when to use an alternative: 'For scored historical performance use get_forecast_track_record.' It also clarifies the optional node_id filter with examples, indicating the intended use case for querying specific hubs or nodes.

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