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

Annotations already establish the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false) and are not contradicted. The description adds a genuinely valuable behavioral note: pips are signed by actual price direction and are not pre-adjusted for side, a convention trap an agent would otherwise get wrong.

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 tight sentences: what it computes, its sign caveat, when to use it, and the return shape. Front-loaded with the core purpose and no filler, though the return-shape sentence could be trimmed since it is mechanically enumerable.

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?

No output schema exists, so the description compensates by naming the return fields (deltaPips, exitPrice, pnlQuote). For a 5-required-param read-only workflow tool the description covers purpose, trigger, and result shape adequately; only sibling differentiation is unaddressed.

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%, so the baseline is 3, but the description earns a bump by clarifying deltasPips semantics (signed, side-agnostic) — precisely the parameter most likely to be misused. It also ties the single-position-size constraint to units without re-listing schema text.

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+scope: PnL over a range of hypothetical price moves for a single forex position, long or short. An agent can tell this apart from most siblings, though nothing in the text distinguishes it from close relatives like run_forex_pnl or run_scenario_planning.

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 ("what if price moves X pips in either direction?") which is exactly the user phrasing that should select this tool. It stops short of naming an alternative or a when-not condition, which matters given the dense forex sibling cluster.

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