opa_get_history

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

No annotations provided, so description carries the burden. It explains return values (high, low, average, change, count) and clarifies period meanings with hour/day equivalents. However, it doesn't mention idempotency, side effects, or potential errors, which is adequate but not exemplary.

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 concise sentences: purpose, usage guidance, and return-plus-period details. No waste, front-loaded with essential information.

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 no output schema and no annotations, the description covers purpose, usage, input details, and return structure. It differentiates from siblings and provides enough context for a simple historical data query. Minor omission: no mention of data source or limitations.

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 descriptions for both parameters. The description adds context by explaining period values with equivalent durations (e.g., 'day (24h)'), but this is marginal beyond what the schema provides. Baseline is 3.

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 'Get historical price data for a commodity over a time period', specifying the verb and resource. It also lists return fields, distinguishing it from siblings like opa_get_price (current price) and opa_compare_prices.

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?

Explicitly states when to use: 'when the user asks about price trends, historical prices, or how a commodity has performed over time.' While it doesn't explicitly list exclusions, the context signals (sibling tool names) imply alternatives for non-historical queries.

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