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

The description adds significant behavioral context beyond the readOnlyHint: it walks the order-book ladder, returns a verdict (clean|degraded|cannot_fill), and warns about thin_legs and forced_directional_risk. It even discloses the dominant loss mode in arb-bot P&L. 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 long but tightly packed—every sentence adds functional or warning value. It uses mode-based organization (SINGLE-MARKET vs BASKET) and front-loads the purpose. However, the density could be slightly reduced without losing critical information, hence a 4.

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 takes on full responsibility for explaining return values. It enumerates all major fields for both modes (top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, theoretical_sum, realizable_sum, capture_ratio, profit_usd, thin_legs, max_clean_notional_usd, forced_directional_risk). It also covers edge cases like partial fills and the need for a market or event parameter.

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?

Even though schema coverage is 100%, the description enriches each parameter with mode-specific semantics. For example, size_usd is 'max spend on buys, target proceeds on sells' in single-market mode and 'settlement notional S (shares per leg; each share pays $1)' in basket mode. Side defaults are explained for both modes.

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 verb and resource: 'Realizable-vs-theoretical edge check against live CLOB order-book depth.' It clearly distinguishes between single-market and basket modes and names sibling tools (polymarket_arbitrage, polymarket_edges), making its purpose unambiguous.

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?

Explicit usage guidance is provided: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains when not to rely on theoretical edge and identifies risks (partial basket fills convert arb into directional position).

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