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

Annotations already indicate read-only, idempotent, non-destructive behavior. Description adds value by detailing the order book traversal, return fields like slippage_pp and verdict, and warnings about partial fills and directional risk. No contradictions. Lacks some specifics like rate limits or performance but is transparent enough.

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?

Well-structured with clear sections for single-market and basket modes. Front-loaded with purpose. Some redundancy (e.g., repeated use of 'realizable vs theoretical' but justified given complexity). Could be slightly more concise, but every sentence adds value.

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 no output schema, description thoroughly covers return values for both modes: includes specific fields (top_of_book, vwap, slippage, shares_filled, max_fillable, verdict for single; theoretical_sum, realizable_sum, capture_ratio, profit, per-leg detail, thin_legs, max_clean_notional, forced_directional_risk for basket). Also explains the dominant loss mode, making it complete for safe usage.

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 covers all 4 parameters with descriptions. Description adds additional meaning: explains default auto side for basket, interprets size_usd differently for buys vs sells and for single-market vs basket, and clarifies settlement notional concept. Enhances understanding beyond schema.

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?

Clearly states it performs a realizable-vs-theoretical edge check against live order book depth. Distinguishes single-market and basket modes, and lists specific return fields. Differentiates from siblings like polymarket_arbitrage and polymarket_edges by its simulation/check role.

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 advises using this tool before acting on polymarket_arbitrage signals or trades above ~$500. Explains consequences of not using it (theoretical overrun not capturable, partial basket fills cause directional risk). Provides clear when-to-use and reasoning.

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