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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false. The description adds meaningful behavioral context beyond those: the result is time-decaying ('net sell-pressure read that decays in hours'), source-specific ('CDP-indexed events'), chain-specific ('over x402 on Base'), and cost/auth-related ('Priced $0.04 per call', 'No wallet or API key required'). No contradiction with annotations.

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 longer than minimal but every part earns its place: purpose, differentiation, semantics, cost, and access requirements. The rhetorical opening and 'Flow, not snapshot' framing are useful for selection, though the text is slightly dense and could be tightened.

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?

Given moderate complexity, full schema coverage, and an output schema, the description is complete for correct invocation. It provides the required input, optional window context through the schema, chain, pricing, and authentication model, so an agent can decide whether and how to call this tool.

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 description coverage is 100%, so the schema already documents both 'address' as 'Token contract address' and 'hours' with default/maximum. The description only re-emphasizes that address is required and implies a 24h window, but it does not materially add beyond the schema. Baseline 3 is appropriate.

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 states a specific verb plus resource: it reports 'the largest transfers of a Base token in the last 24h' and classifies them by whale behavior. It also explicitly distinguishes itself from holder_forensics with 'Flow, not snapshot', so an agent can separate this from sibling tools without opening schemas.

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 a clear decision cue: it 'Complements holder-forensics' by answering 'is anyone dumping now' versus 'who could dump'. It also specifies the required address input. It does not enumerate explicit when-not-to-use conditions, but the contrast with holder_forensics effectively routes an agent.

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