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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds one useful non-obvious fact — 'numbers follow the connected account' — indicating results are account-scoped, but it says nothing about the freshness/lag behavior that the schema's 'fresh' parameter reveals (the hour-behind default), nor about return shape.

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?

Two short sentences, zero padding, with the subject ('Implied volatility board') front-loaded and the contents enumerated second. Nothing repeated from the title or annotations.

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?

With no output schema, the description does sketch the payload (gauge list, percentile, latest plus history), which is what an agent needs to judge relevance. Missing only minor return details such as row/field shape and default limits, which the absence of an output schema leaves unstated.

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 description coverage is 100%, so all three parameters are already documented in the schema, including the credit cost and lag for 'fresh' and the plan-dependent depth for 'since'. The description's 'Newest reading plus past boards' lightly frames the paging model but adds no syntax or defaults beyond the schema, so baseline 3 applies.

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?

Names a specific resource ('implied volatility board') and enumerates its contents (VIX and other vol gauges, one-year percentile, newest reading plus past boards). The topic specificity cleanly separates it from topic-specific siblings like get_fx_board, get_rates_and_curve, and get_market_context without opening any schema.

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?

There is no statement of when to use this board versus get_series, get_market_context, or the other board tools, and no prerequisites. The only usage-adjacent hint is 'Newest reading plus past boards,' which implies the since/limit window but never says so explicitly.

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