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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely non-obvious operational context: a $0.003 USDC per-call x402 charge, which affects whether an agent should call it speculatively. It stops short of return format or rate limits, but the cost disclosure is real added value.

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?

One sentence, front-loaded with the source and coverage, then the horizon, then the cost. No filler; every clause (source, commodities, horizon, latest actual, 12-month change, price) carries information an agent needs.

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?

With no output schema, the description carries the return-shape burden and does so: monthly series plus latest actual and 12-month change. Read-only safety comes from annotations and cost is stated, so the only thin spot is history_months, which is a minor gap for a 0-required-param 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 50%: the indicators parameter is documented in-schema, and the description enumerates the same commodity list, adding little. history_months has no description anywhere, and the '12-24 months' horizon only loosely hints at its meaning. Baseline 3 is appropriate given the split coverage.

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?

States a specific verb+resource with scope: an EIA Short-Term Energy Outlook price forecast covering gasoline, diesel, WTI, Brent, Henry Hub gas and residential electricity over a 12-24 month horizon. The 'forecast' framing cleanly separates it from the sibling price tools (energy_electricity_prices, energy_gas_prices, energy), which read actuals rather than projections.

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 makes the use case (forward-looking price outlook) obvious by implication, but never states when to prefer it over the spot-price siblings or any exclusions. An agent must infer the routing decision from the word 'forecast' alone.

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