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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description earns credit for disclosing the return shape (array of { deltaPct, exitPrice, netPnl, roe }), which no output schema provides and which tells the agent exactly what comes back.

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 compact clauses — what it does, when to use it, what it returns — front-loaded with no filler. Every sentence earns its place.

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, description of the returned fields is the key missing piece and it is supplied. The conversion semantics for inverse contracts are left to the schema, and edge-case behavior (e.g. -100% on inverse) is undocumented, keeping it short of 5.

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 86%, so the schema already carries the parameter meaning, including delta bounds and the inverse-vs-linear contract nuance. The description's example deltas merely restate what the schema shows, adding no new semantics.

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?

States a specific verb+resource ('Run a scenario analysis: compute PnL for multiple price-change percentages at once'). The 'multiple percentages at once' framing separates it from single-point siblings like run_pnl_planning or run_breakeven_planning, though no sibling is named explicitly.

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?

Gives a concrete trigger phrase ('show me my P&L if BTC moves -10%, -5%, +5%, +10%'), which clearly signals when to reach for this tool. No explicit when-not or named alternative (e.g. vs run_pnl_planning) is offered, so it stops short of 5.

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