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

With no annotations, the description carries the full behavioral burden. It usefully discloses the data source (EIA WPSR), the cadence (weekly), and the derived metrics returned per series (build/draw, YoY, 5-year average). It does not state units, how quickly data appears after the EIA release, or any access/rate constraints, so coverage is partial.

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 dense sentences, front-loaded with the source and scope, with the enumerated series doing real work. The closing disclaimer is short and purposeful for a financial-data tool. No 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?

With no parameters and no output schema, the description must convey what comes back, and it does so concretely by listing the five stock categories and the three comparative metrics. It stops short of units, release lag, and temporal coverage, which an agent would still want.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline of 4 applies. Schema coverage is nominally 100% but vacuous given an empty properties object.

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 names the exact resource (U.S. oil inventories from the EIA Weekly Petroleum Status Report) and enumerates the specific series covered: commercial crude, Cushing, SPR, gasoline, distillate. That is far more specific than a bare name restatement, but it never distinguishes itself from nearby siblings such as oil_supply or oil_markets, leaving the agent to infer the boundary.

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?

There is no when-to-use, when-not-to-use, or alternative-tool guidance. The only usage-adjacent sentence is the disclaimer 'Data, not trading advice,' which frames tone rather than routing. An agent choosing between this and oil_supply, oil_prices, or oil_markets gets no help.

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