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

Annotations already establish readOnly/idempotent/non-destructive, and the description adds real value on top: a tier/auth requirement ('Pro required'), a negative behavioral clarification (it is not an eth_call of the swap), and a conditional action rule. It does not cover latency, rate limits, or full response shape, keeping it short of a 5.

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, no filler, and the most important constraint (this is a pre-check, not a swap call) is front-loaded before the Pro requirement and the failure-handling rule.

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?

With no output schema, the description partially compensates by naming the key return field ('executable') and prescribing behavior when it is false. It still leaves the rest of the response and several optional session/amount parameters unaddressed, so it is good but not fully self-contained.

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% across all 7 parameters, so the schema already documents tokenIn/tokenOut/notionalUsd/slippageBps and the amount variants. The description only loosely gestures at policy/notional checking and adds no syntax, format, or default detail beyond the schema, which is the expected baseline 3.

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?

Names a specific operation ('pre-trade check') on a specific chain (4663) and enumerates exactly what it evaluates: allowlist, policy limits, and quote executability. It also explicitly scopes itself against a sibling behavior ('This is not an eth_call of the swap'), so an agent can separate it from stocktoken_quote and stocktoken_execute_plan.

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 clear precondition ('Pro required') and a decisive post-condition ('If executable is false, stop and do not promise a fill'), which tells the agent how to act on the result. It stops short of naming the alternative tools it precedes (e.g., execute_plan or quote) by name, so routing is implied rather than explicit.

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