Options implied-volatility surface and 25-delta skew

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a data-source detail ('from the daily Deribit chain') and what the returned surface contains, but does not disclose potential limitations such as data lag, snapshot timing, or how open-world data affects results. This is adequate but not rich.

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?

The description is a single sentence that front-loads the usage trigger and then compactly enumerates the return components. Every phrase adds value, and no filler or redundant restatement of the title appears.

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?

Despite lacking an output schema, the description spells out the major return fields: IV surface by expiry/moneyness, per-expiry ATM and 25-delta put/call IV, skew, butterfly, and constant-30d history. With only one optional parameter and annotations covering read-only/open-world behavior, an agent has enough to call and interpret the tool correctly.

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% for the single optional currency parameter, so the schema already documents it fully. The description does not need to repeat parameter details and adds no extra meaning beyond the schema; the baseline of 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?

The description states a specific verb ('get') and resource ('options implied-volatility surface and 25-delta skew') and enumerates the exact types of user questions it addresses. It clearly distinguishes itself from the many sibling tools by focusing on IV, skew, and term structure.

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?

The description explicitly opens with 'Call this when the user asks about...' and lists concrete use cases like skew, put versus call IV, and downside protection cost. It does not name alternatives or state when not to use the tool, but the usage context is clear enough for an agent to route correctly.

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