opa_get_market_brief

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

No annotations provided, so description carries full burden. It discloses API key requirement, request counting, per-tier code limits, and the effect of the narrative parameter. However, it doesn't mention error handling or rate limits beyond tier limits.

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?

Single paragraph with logical flow: main purpose, usage guidance, details on parameters and constraints. Each sentence adds value; could be slightly more concise but not overly verbose.

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 moderately complex tool with no output schema, the description covers what it returns, prerequisites, limits, and alternatives. Missing details on response format but acceptable given output schema absent.

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% but description adds value: clarifies that codes accept natural language or API codes, and explains the narrative parameter's effect and default. This goes beyond the schema descriptions.

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 it provides a multi-commodity market brief with specific data points (spot prices, 24h changes, forecasts, spreads). It distinguishes itself from siblings like opa_get_price (single price) and opa_create_price_subscription (recurring monitoring).

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 says when to use (market snapshot, morning brief, at-a-glance read) and when not to (single price -> opa_get_price; recurring -> opa_create_price_subscription).

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