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

The description discloses several behavioral traits not captured in annotations: it 'walks the ladder,' requires one of market or event, returns a verdict, and warns about partial fills creating 'unhedged directional position.' It also adds safety context (forced_directional_risk, thin_legs) and explains the consequences of misuse, which annotations alone do not provide.

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 appropriately so for a dual-mode tool with complex return fields. It is front-loaded with the core purpose, then logically broke into SINGLE-MARKET, BASKET, and usage guidance; no sentence is filler. Could be slightly tightened but structure earns high marks.

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?

Even without an output schema, the description enumerates every important return field for both modes (top_of_book, vwap_fill_price, slippage_pp, capture_ratio, profit_usd, thin_legs, etc.), mentions edge cases (partial fills, thin books, forced directional risk), and clarifies defaults and clamps. It is fully self-contained for an agent to know what to expect and when to use it.

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% (baseline 3), but the description adds meaningful semantics beyond raw schema: size_usd is 'max spend on buys, target proceeds on sells' for single-market and 'settlement notional' for basket; side has explicit default behavior per mode. It also clarifies the mutually exclusive requirement of market vs event, which the schema only implies.

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 opens with a specific verb-resource: 'Realizable-vs-theoretical edge check against live CLOB order-book depth.' It clearly distinguishes three modes (single-market, basket, and auto), and the unique value proposition is evident from the start, establishing it as distinct from 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?

Usage guidance is explicit and actionable: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains the risk rationale (thin books, unhedged directional positions), giving agents clear criteria for when this tool is required versus optional.

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