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

Annotations already indicate read-only and idempotent behavior, but the description adds substantial behavioral detail: it walks the CLOB ladder, returns a verdict, calculates capture ratio, and flags partial basket fill risk. It also clearly warns that 'partial basket fills convert an arb into an unhedged directional position,' which is critical risk context beyond the 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 densely packed, using clear section markers (REQUIRES, SINGLE-MARKET, BASKET) and front-loading the purpose. Every sentence adds necessary operational or risk context; the length is justified by the tool's two modes and many return fields.

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 fully enumerates return values for both modes, including nuanced items like thin_legs[], max_clean_notional_usd, and forced_directional_risk. It also covers parameter behavior, required modes, and real-world loss scenarios, making it sufficiently complete for correct invocation.

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?

Although schema description coverage is 100%, the description greatly enriches parameter understanding. It explains mode-specific semantics: size_usd means 'max spend on buys, target proceeds on sells' in single-market mode but 'settlement notional' in basket mode, and side defaults differ (buy_yes vs auto). This is meaningfully more than the schema provides.

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 action: 'Realizable-vs-theoretical edge check against live CLOB order-book depth,' clearly defining the tool's core function. It explicitly distinguishes itself from sibling tools like polymarket_arbitrage and polymarket_edges by positioning itself as a pre-trade risk validation step.

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 context is explicit: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' This provides a concrete trigger and threshold, making it clear when this tool is the appropriate choice versus acting directly on arb/edge signals.

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