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

Annotations declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds substantive behavioral detail: it walks the ladder, returns fields like top_of_book, vwap_fill_price, slippage_pp, shares_filled, max_fillable_usd, verdict; in basket mode it computes theoretical_sum vs realizable_sum, capture_ratio, profit_usd, per-leg fills, thin_legs[], max_clean_notional_usd, and forced_directional_risk. It also warns about partial fills converting an arb into an unhedged directional position, going well beyond the annotation safety profile.

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 well-structured with uppercase section markers (REQUIRES, SINGLE-MARKET, BASKET) and front-loads the core purpose. Every sentence provides distinct information, though the length could be trimmed by removing some parallel phrasing between modes.

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?

There is no output schema, so the description must enumerate return values; it does for both modes. It also covers defaults for side and size_usd, the clamp range, and the tool's intended place in the workflow relative to sibling tools. For a tool with 4 parameters, no output schema, and two distinct modes, the description is complete.

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?

The schema has 100% coverage with detailed descriptions for each parameter. The description adds the critical constraint 'REQUIRES one of market (single-market mode) or event (basket/partition mode)' and clarifies size_usd's dual interpretation, though the schema already covers most parameter semantics. The added constraint is valuable for correct invocation.

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 verb-object: 'Realizable-vs-theoretical edge check against live CLOB order-book depth.' It distinguishes this tool from siblings like polymarket_arbitrage and polymarket_edges by focusing on whether theoretical edges are actually capturable on the order book.

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 explicitly states when to use: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500' and explains why (theoretical overround on thin books is not capturable, partial fills create directional risk). It names alternatives and provides a clear trigger.

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