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

Annotations already indicate read-only, idempotent, non-destructive. The description adds detailed behavior: walks the order book ladder, returns top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, verdict, and for baskets: theoretical_sum vs realizable_sum, capture_ratio, profit_usd, thin_legs, forced_directional_risk. No contradiction with annotations.

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 well-structured with clear sections for single-market and basket modes, uses bold for key terms, and front-loads the purpose. While lengthy, every sentence adds value; minor tightening possible but still efficient.

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?

Given complexity (two modes, no output schema), the description is very complete. It covers both modes, explains return fields in detail, and warns about forced directional risk and thin legs. No output schema exists, so description must and does fill that gap.

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% with descriptions for all 4 parameters. The description adds context beyond schema, e.g., for size_usd it clarifies interpretation for buys vs sells and basket mode; for side it explains default auto behavior. Enriches understanding but schema already provides basic info.

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 clearly states it performs a 'realizable-vs-theoretical edge check against live CLOB order-book depth' and differentiates between single-market and basket modes. It also distinguishes itself from sibling tools like polymarket_arbitrage and polymarket_edges by specific usage guidance.

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 says 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500' and explains why (theoretical overround not capturable on thin books, partial fills create directional risk). Provides clear when-to-use and alternatives.

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