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

The description goes well beyond the readOnly/openWorld/idempotent annotations. It discloses that the tool 'walks the ladder,' returns a verdict (clean|degraded|cannot_fill), and – crucially – warns that partial basket fills convert an arb into an unhedged directional position. These are non-obvious behavioral traits that an agent needs to know before acting. 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?

Although the description is lengthy, it is front-loaded with the core purpose and then structured logically into single-market vs. basket modes. Every sentence adds distinct value: parameter semantics, return fields, verdict meaning, risk warning, and usage timing. No filler or redundancy; the density is necessary for a tool with two modes and complex 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?

With no output schema, the description takes on the full burden of explaining return values, which it does thoroughly – listing 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, and forced_directional_risk. It also covers parameter interplay and edge-case risk, making the tool's behavior fully understood without an output schema.

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%, and the parameter descriptions in the schema already fully explain each parameter's meaning in both modes. The tool description largely repeats this information (e.g., side modes, size_usd interpretation) rather than adding significantly new semantics. It provides organizational context but no new per-parameter detail beyond the schema.

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 clear, specific verb phrase: 'Realizable-vs-theoretical edge check against live CLOB order-book depth.' It distinctly separates single-market and basket modes, and the tool is clearly differentiated from sibling tools like polymarket_arbitrage and polymarket_edges, which are about finding or listing edges, not verifying capturability.

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 usage instruction: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains why this timing is critical, citing thin books, partial-fill risk, and the dominant loss mode in arb-bot P&L, which gives clear context for when this tool is the right alternative.

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