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

With no annotations, the description carries the full burden. It discloses key behavioral nuances: Hyperliquid perp includes realized plus unrealized snapshot, EVM/all reports separate sections and never sums, and named chains report realized PnL only. This goes beyond the obvious read-only nature and helps set expectations, though exact output fields are left to the output schema.

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 five sentences long, with the main point up front and chain-specific rules logically grouped. Every sentence adds value, though the final sentence is mildly redundant with the first. Still, it is well-organized and appropriately sized for the tool's complexity.

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 an output schema, so return values are covered separately. The description addresses the main decision points (which chain to query, what to expect for each), making it complete enough for an agent to invoke correctly. It omits edge cases like invalid addresses or unsupported chains, but these are not critical for successful use.

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 description adds significant meaning to the 'chain' parameter by detailing its behavioral implications ('chain='hyperliquid'' vs 'chain='all'/'evm''). However, it does not elaborate on walletAddress or dateRange beyond 'input address' and 'over a time period', leaving those semantics to the schema. With schema coverage indicated at 0%, this is a partial but incomplete compensation.

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 primary function: 'Get aggregate stats of overall realized PnL for the input address.' This specific verb+resource combination distinguishes it from siblings like wallet_pnl_for_token, which targets token-specific PnL. The chain-specific behavior is also summarized, further clarifying scope.

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 context: 'Use this tool for analysing the performance of the wallet over a time period.' It also explains how chain choices affect results, helping the agent decide which chain to pass. It does not name alternative tools explicitly, but the timing and scope guidance are clear.

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