OilPriceAPI

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

No annotations provided, so description carries full burden. Compensates by describing return structure ('Returns a table of contract months...plus market structure analysis'), which is valuable given no output schema. However, lacks operational details like rate limits, authentication requirements, or explicit read-only safety confirmation.

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 sentences efficiently structured: [1] Purpose, [2] Usage trigger, [3] Return value. Zero waste, front-loaded with action verb, appropriate length for tool complexity.

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?

Given single optional parameter and no output schema, description adequately covers essential aspects: functionality, usage context, and return format. Minor gap: does not mention default value (BZ) or explicitly reference the contract parameter in the description text, though schema covers this.

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% with clear enum descriptions ('BZ = Brent crude, CL = WTI crude'). Description implies the scope ('all contract months') but does not add syntax or semantic details beyond the schema. Baseline 3 appropriate when schema is self-documenting.

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?

Specific verb 'Get' + resource 'futures forward curve' + scope 'full...across all contract months'. Clearly distinguishes from siblings like opa_get_futures (likely spot/single contract) and opa_get_history via the forward curve/term structure focus.

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?

Explicit when-to-use: 'Use when the user asks about the forward curve, contango/backwardation, or term structure.' Lacks explicit when-not-to-use or named alternatives, but the specific domain language provides clear contextual boundaries.

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