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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). Beyond that, the description discloses scope limits – no venue fee lookup, no execution/liquidation/outcome prediction – and the zero-fee assumption on omission, which is genuinely useful context an agent could not infer from annotations alone.

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?

Front-loaded with the core computation, then assumptions, then exclusions in a compact run of sentences with no filler. Some content duplicates what the schema already states, which slightly dilutes the value of each sentence.

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?

The tool is moderately complex (6 params, nested fees), and the description supplies direction derivation, fee-assumption behavior, and unsupported operations. With annotations, full schema coverage, and an output schema handling return values, the description is essentially complete for correct invocation.

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%, so the schema already documents every parameter, including the fee nesting and the entry/stop direction derivation. The description largely restates those same facts (distinct fee percentages, direction from entry/stop) without adding new semantics, so the baseline 3 applies.

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 specific computations (gross and fee-adjusted reward-to-risk, loss/profit per unit, breakeven win rate) for a well-defined object (a linear trade with known entry, stop, target). This is clearly differentiable from calculate_position_size and analyze_trade_performance 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?

Gives explicit when-to-use ("Use for questions about a planned R ratio or how fees change it") and explicit exclusions ("Does not fetch venue fees or predict execution, liquidation, or trade outcomes"). It stops short of naming the sibling tools as alternatives, so it misses the top mark.

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