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 adds useful behavioral context by stating this is a pure fee-only computation and naming the returned fields (breakevenPrice, totalFees) in the absence of an output schema; it could say more about fee assumptions, but that is largely in the schema.

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 front-loaded sentences with zero waste: purpose, then when-to-use, then when-not-to-use with alternatives, plus a return note. Every sentence earns its place, including the emphatic scoping phrase that prevents over-application.

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?

For a bounded 6-parameter read-only computation, the description supplies the selection boundary and the return fields despite there being no output schema, while the schema fully documents parameters and defaults. An agent has everything needed to call it 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%, including enum explanations and inverse/linear semantics, so the schema does the heavy lifting. The description adds no parameter-level detail beyond what the schema already provides, making the baseline 3 appropriate.

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 verb+resource ('Calculate the break-even exit price') and scopes it tightly ('this alone, nothing else'). It explicitly distinguishes itself from workflow.run_risk_reward and workflow.run_pre_trade_check, so an agent can select it without opening any 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 an explicit positive trigger (user asks only 'what price do I need to just break even?') and explicit exclusions with named alternatives for the stop/target or full-safety-check cases. Nothing about when-not-to-use is left to inference.

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