Get Futures Price

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

Annotations already carry readOnlyHint=true and openWorldHint=true, covering the non-destructive and open-ended input nature. The description adds meaningful context by requiring an eligible account entitlement and clarifying that the API response is authoritative. It does not discuss return format, rate limits, or error handling, but for a simple read-only price tool this is a reasonable augmentation.

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?

Four sentences with zero waste: the first delivers the core action and scope, the second specifies acceptable inputs, the third routes to the correct alternative, and the fourth provides entitlement and authority context. The most critical information is front-loaded.

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, read-only price tool, the description covers purpose, input guidance, alternatives, entitlement, and authority. The only notable gap is the lack of an explicit description of the response shape, but the tool's simple purpose and the absence of an output schema make this a minor omission rather than a critical flaw.

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 schema description coverage is 100%, fully documenting the contract parameter with both canonical slugs and legacy compatibility inputs. The prose description repeats these same details without adding significant new meaning, so this dimension settles at the baseline 3 rather than higher.

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 opens with a specific verb 'Get' and a precise resource: 'the latest front-month futures contract price for energy commodities.' It also lists the canonical instrument slugs, making the tool's scope concrete, and explicitly differentiates itself from the sibling opa_get_futures_curve by naming what that tool does instead.

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 clear when-to-use guidance by naming opa_get_futures_curve as the alternative for forward curves and directing users to opa_get_plans for access and pricing confirmation. It also states the prerequisite 'eligible account entitlement' and explains that compatibility inputs are accepted, so an agent knows exactly how to route between the tool and its siblings.

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