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

With no annotations, the description carries the behavioral burden. 'Get PnL stats' and 'analysing' signal a read-only analytics operation, and the chain rule discloses a non-obvious input behavior. However, it does not cover permissions, rate limits, data freshness, or what happens for unsupported chains; the output schema covers return shape, so this is adequate but not rich.

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 first sentence states the action, the second rephrases it as a use case, and the third gives essential chain/tokenAddress guidance. One sentence is somewhat redundant ('Get...' vs 'Use this tool for analysing...'), but the length is appropriate and the critical chain detail is front-loaded.

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?

Together with the nested schema definitions for dateRange and showRealized, the description covers the main invocation decisions: what wallet/token/date range to supply and how the chain field changes tokenAddress interpretation. The output schema removes the need to describe return values. Missing explicit alternative routing to wallet_pnl_summary is the main gap.

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 front-loads the trickiest parameter behavior: on hyperliquid, tokenAddress is the perp SYMBOL ('BTC', 'HYPE', 'xyz:CL'), while every other chain expects a contract address. It also contextualizes walletAddress/tokenAddress/dateRange through 'traded by the input address during a specific date range.' Although nested schema properties already document this, the description makes the key distinction prominent and compensates for the sparse top-level request 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 specific verb and resource: 'Get PnL stats for a specific token traded by the input address during a specific date range.' 'Specific token' and 'input address' clearly separate it from the sibling wallet_pnl_summary and from token-wide or address-wide tools, so an agent can identify the right operation without opening the schema.

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?

'Use this tool for analysing the performance of the wallet for the specific token over a time period' gives a direct use case, and the chain note gives concrete invocation guidance for the hyperliquid exception. It stops short of naming sibling alternatives or saying when not to use it, so it misses the explicit exclusion that would earn a 5.

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