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

Beyond the annotations (readOnly, openWorld, idempotent), the description discloses substantial behavioral traits: it walks the order-book ladder, returns specific fields like top_of_book, vwap_fill_price, slippage_pp, and shares_filled, and warns about forced_directional_risk. It also explains the consequences of partial basket fills, providing context annotations alone do not convey.

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 front-loaded with the core purpose and structured by mode (SINGLE-MARKET, BASKET). Given the absence of an output schema, listing return fields is necessary. While it could be tightened slightly, every sentence earns its place, and the organization aids readability.

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 has two modes, four optional parameters, and no output schema. The description fully covers both modes, parameter interpretations, return values (theoretical_sum, capture_ratio, thin_legs, etc.), and usage context. It also addresses failure modes and risk, making it complete for an agent to decide when and how to invoke the 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?

Although schema coverage is 100%, the description adds significant semantic depth. For size_usd, it distinguishes between single-market ('max spend on buys, target proceeds on sells') and basket ('settlement notional S — shares per leg'). It also explains the side parameter's mode-dependent defaults and auto behavior based on partition sum, enriching the 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 the tool's purpose: 'Realizable-vs-theoretical edge check against live CLOB order-book depth.' It distinguishes itself from sibling tools like polymarket_arbitrage and polymarket_edges by explicitly positioning itself as a pre-trade validation check. The verb 'check' plus the resource 'CLOB order-book depth' makes the function 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?

The description provides explicit when-to-use guidance: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains two distinct modes (single-market vs. basket) and when each applies, including the rationale that theoretical overround on thin books is not capturable and partial basket fills can create unhedged directional risk.

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