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

With annotations declaring readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, the description adds extensive operational detail: walks the ladder, returns top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, verdict, per-leg fill detail, thin_legs, and forced_directional_risk. This far exceeds the annotations' baseline and aligns with them, though it doesn't address potential errors or rate limits, which is acceptable given the rich annotation set.

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?

Although long, the description is tightly structured with labeled modes (SINGLE-MARKET, BASKET) and enumerates return fields. Every sentence carries operational weight—defaults, choices, risk warnings—without tautology or filler. The density is appropriate for a complex tool with dual modes and many outputs.

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?

The tool is complex (two modes, 4 parameters, no output schema), but the description compensates comprehensively: it explains both modes, all parameters, all return fields (top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, verdict, theoretical_sum, realizable_sum, capture_ratio, profit_usd, per-leg fill detail, thin_legs[], max_clean_notional_usd, forced_directional_risk), and usage context. It is self-contained for an agent to use 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 100%, so baseline is 3. The description adds semantic depth by clarifying that size_usd means 'max spend on buys, target proceeds on sells' in single-market mode and 'settlement notional' in basket mode (shares per leg, each paying $1 at resolution). It also documents the default size (1000) and clamp range, enhancing the schema's concise 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 states a specific purpose: 'Realizable-vs-theoretical edge check against live CLOB order-book depth,' and clearly delineates single-market vs basket modes. It distinguishes itself from sibling tools like polymarket_arbitrage and polymarket_edges by focusing on fill risk rather than arbitrage detection or edge calculation.

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 prescribes when to use: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains why (theoretical overround on thin books is not capturable, partial basket fills create unhedged directional positions), going beyond simple timing to give strategic rationale.

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