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

While annotations already indicate read-only/idempotent/non-destructive, the description adds substantial behavioral context: it walks the order-book ladder, returns specific fields for both modes, names legs likely to strand the user unhedged, and warns about the dominant loss mode. No contradiction with annotations exists.

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 long, the description is front-loaded with the core purpose and each sentence earns its place, covering modes, defaults, return values, and risk warnings. The use of SINGLE-MARKET/BASKET/USE THIS segments provides structure without redundancy.

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?

For a tool with no output schema, the description is exceptionally complete, listing all return values for both modes, explaining edge cases like thin legs and forced directional risk, and placing it in workflow context relative to sibling tools. No critical information appears missing.

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%, but the description goes well beyond the schema by interpreting size_usd differently per mode ('max spend on buys, target proceeds on sells' vs 'settlement notional S'), explaining the side default logic in basket mode, and clarifying the meaning of event/market slugs. This adds real value to parameter understanding.

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 and resource: 'Realizable-vs-theoretical edge check against live CLOB order-book depth,' clearly stating the tool's function. It further distinguishes itself from siblings by explicitly naming polymarket_arbitrage and polymarket_edges as triggers, and by detailing both single-market and basket modes.

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 gives explicit usage guidance: 'USE THIS before acting on any polymarket_arbitrage SELL/BUY-EVERY-LEG signal or any polymarket_edges trade above ~$500.' It also explains why, citing the risk of thin-book overround not being capturable and partial basket fills converting arbs into unhedged directional positions.

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