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

Annotations already declare readOnlyHint/openWorldHint/idempotent/destructive, so the bar is lower. The description still adds value: it enumerates the specific rules and models applied (2026 US day-trading rules, square-root impact with crowding) and clarifies the tool performs a pure computation with no broker or account access.

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 sentences, front-loaded with the check and the scope of the model, followed by the isolation constraint. Dense but no filler; the second sentence's boundary statement 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?

An output schema exists, so return-value explanation is not needed. For a 15-parameter modeling tool the description conveys the model's components and its read-only, offline nature, though it leaves the roughly one-third of undocumented parameters to the schema alone.

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 67%, a middle band where the schema documents most inputs on its own. The description gestures at parameter domains (broker order-rate limits, impact, cost capacity) but gives no syntax, units, or defaults beyond what the schema already states, so it neither compensates for the gap nor repeats the schema.

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?

Specific verb (check) and resource (a trading plan) with a tightly bounded scope — broker limits, day-trading rules, market impact, and cost capacity — that reads distinctly from the validate_* and backtest_strategy siblings. It does not, however, explicitly name any sibling to differentiate itself from them.

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?

'Check a trading plan before it trades' gives a clear usage context (pre-trade feasibility screening) and the closing clause states a boundary (never contacts a broker, never sees an account). No explicit when-not-to-use or routing to an alternative sibling is provided.

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