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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is low, and the description still adds real context: no inputs, values reported as fractions of equity and USD, real money and sandbox counted separately, and pending limit increases included in the result. It stops short of describing how stale the usage figures are or when limits reset, which would be the remaining behavioral detail.

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 covered limit types are front-loaded in the first clause, followed by units, scope, exclusion and next step as compact fragments. No sentence is redundant and there is no filler.

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 values need not be explained in prose. Between the enumerated limit types, usage fractions, units, sandbox separation, pending increases, the permission-tool exclusion and the next-step pointer, an agent has everything needed to call and interpret this tool.

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?

Zero parameters, so the baseline is 4. The description confirms 'No inputs', which is consistent with the empty schema and prevents an agent from inventing arguments.

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 names a specific resource (global risk limits) and enumerates exactly what it covers: per-trade risk, daily/weekly/monthly loss, drawdown, leverage, open positions, with usage fractions per limit plus pending limit increases. It also explicitly separates itself from get_my_trading_permissions, so an agent can distinguish it from siblings without opening a 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?

It gives concrete trigger conditions ('when a trade was rejected by a user-level limit or before planning several trades'), an explicit exclusion with the correct alternative ('Not for this agent's own permissions (use get_my_trading_permissions)'), and a follow-up step ('Next: size_position_by_risk').

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