OilPriceAPI

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 adds that the tool 'Returns current inventory levels with changes,' which hints at the output structure. However, it omits details about data freshness, potential rate limits, or explicit read-only safety guarantees that would be helpful without annotation coverage.

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?

Three well-structured sentences with zero waste: purpose declaration, usage trigger, and return value description. Information is front-loaded and immediately actionable.

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 complete schema coverage and no output schema, the description adequately covers the tool's function, usage context, and return value. It could enhance completeness by describing the return structure in more detail, but given the low complexity, it is sufficient.

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?

With 100% schema description coverage, the baseline is appropriately met. The description mentions Cushing and SPR in the first sentence, reinforcing the parameter semantics, but does not add syntax details, validation rules, or examples beyond what the schema already provides.

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 specific resource (oil storage/inventory levels) and entities (Cushing, SPR) using the verb 'Get'. While it doesn't explicitly name siblings to differentiate, the resource type clearly distinguishes it from price, futures, and production tools in the sibling list.

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?

Provides explicit positive guidance ('Use when the user asks about oil inventories...') covering the key use cases. Lacks explicit negative guidance or named alternatives, but the when-to-use context is clear and specific.

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