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

Annotations already mark this read-only, open-world, idempotent, non-destructive, and the description adds critical behavioral context beyond those flags: it walks the order-book ladder, returns a verdict, and warns that partial basket fills create unhedged directional risk. It also explains that theoretical overround on thin books is not capturable. This exceeds the annotation baseline and contradicts nothing.

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 description is long but front-loaded with a one-sentence summary and then organized by SINGLE-MARKET/BASKET sections. Every sentence adds substantive detail like output fields and failure modes. It could be more readable, but the density is necessary given the tool's complexity.

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 enumerates all return fields and provides both mechanical outputs and risk-related outputs (thin_legs, forced_directional_risk). It covers the real-world failure mode of partial fills, which is essential for using this tool responsibly. The use-case guidance completes the picture.

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 coverage is 100%, but the description adds value by requiring exactly one of market or event, which the schema does not encode as a constraint. It clarifies mode-specific meaning of size_usd (spend vs proceeds vs settlement notional) and default side selection for baskets, going beyond the schema's individual field descriptions.

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 opens with 'Realizable-vs-theoretical edge check against live CLOB order-book depth,' a specific verb+resource that identifies the tool's function. It clearly distinguishes from siblings like polymarket_arbitrage by positioning this as the pre-trade risk check and specifying modes. This is a clear, purposeful statement.

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?

Explicitly instructs 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500,' making the preferred invocation context unambiguous. It also differentiates single-market vs basket modes, implying when each is appropriate. No misleading exclusions are present.

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