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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, covering safety. Description adds behavioral context: 'walks the ladder', returns fill metrics, warns about 'thin_legs' and 'forced_directional_risk'. Clearly explains that this is a check, not an execution, and details risks of partial fills.

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?

Description is relatively long but well-structured with sections for REQUIRES, SINGLE-MARKET, BASKET, and USE THIS. Front-loaded with main purpose. Slightly verbose but justified given complexity of dual modes and detailed return fields. Could be tightened slightly but still clear.

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?

No output schema exists, but description enumerates all return fields for both modes (top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, verdict; basket: theoretical_sum, realizable_sum, capture_ratio, profit_usd, per-leg detail, thin_legs, max_clean_notional_usd, forced_directional_risk). Also covers edge cases and rationale. Very complete for a read-only risk assessment tool.

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 description adds significant value: explains single-market vs basket modes, default values for `side` and `size_usd`, clarifies that `side` auto-detects for basket based on partition sum, and defines `size_usd` as 'settlement notional S (shares per leg)' for basket. All parameters are given contextual meaning beyond schema 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 clearly states it's a 'Realizable-vs-theoretical edge check against live CLOB order-book depth' and distinguishes between single-market and basket modes. It lists specific return values and explicitly names its use case relative to sibling tools like 'polymarket_arbitrage' and 'polymarket_edges'.

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 states when to use: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500'. Explains why (theoretical overround not capturable, partial basket fills convert arb to unhedged directional). Also specifies required parameter: one of `market` or `event`.

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