Price one named structure

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

Annotations already declare readOnlyHint=true and openWorldHint=true, lowering the bar, and the description adds meaningful behavior: pricing against the live book, the effect of offset ('pushes every leg further out of the money... cheaper, needs a bigger move'), and that it returns the same full detail as a proposal. This goes beyond what the annotations or schema alone convey, though it does not discuss failure modes or data freshness.

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 tightly written sentences with no filler. The first sentence front-loads the purpose and primary use case, the second explains the key offset behavior, and the third covers return parity and the prerequisite. Every sentence 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?

For a read-only pricing tool with an output schema and strong parameter descriptions, the description is sufficiently complete. It covers when to use it, how it relates to propose_trades, the prerequisite for getting shape ids, the key offset parameter behavior, and what to expect in the return. Nothing essential is missing for an agent to invoke 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 high (80%), so the schema already documents strategy, contracts, expiry, and offset defaults. The description adds real semantic value by explaining the practical effect of offset (cheaper but needs a bigger move) and reinforcing that strategy ids come from list_strategies. This is above the baseline but not exhaustive for every parameter.

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 states a specific verb ('Price'), a precise resource ('a specific shape at a specific expiry against the live book'), and a clear use case ('when the shape is already decided'). It also differentiates itself from propose_trades by framing this tool as pricing an already-decided/named structure or comparing a variant of a proposal.

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?

The description gives explicit when-to-use guidance: use it when the shape is already decided or to compare a variant of something propose_trades returned. It also names the prerequisite ('Call list_strategies first if you need the shape ids'), which directs the agent to the correct sibling tool.

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