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

Annotations already declare the tool read-only, idempotent, and non-destructive. The description adds that the snapshot is 'public', implying no authentication needed, and notes that precision must be valid for the pair, which is a validation constraint. It does not elaborate on return format or side effects, but the output schema covers that.

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 extremely concise, two sentences, front-loading the primary action. There is no redundant information, and every word contributes to meaning.

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 three parameters and an output schema, the description is minimal. It does not explain that depth and precision are optional, nor their interplay, and it fails to provide any context on when to use this tool. The lack of usage guidance and parameter relationships makes it incomplete for optimal agent selection.

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 67%: symbol and precision have descriptions, depth has none but is constrained by const values. The description adds the dependency of precision on the selected pair, which is useful beyond the schema. It does not add anything for depth, leaving that to the schema's enumerated values.

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 retrieves a public order-book snapshot, which is a specific verb+resource. It is distinct from siblings like market_candles or market_tickers by explicitly mentioning 'order-book', though it does not name an alternative for comparison.

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 no guidance on when to use this tool versus other market data tools. It only states a constraint about precision, without indicating when an agent should prefer the order book over, say, the market snapshot or tickers.

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