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

Despite the readOnlyHint annotation already indicating a read operation, the description adds substantial behavioral context: it explains the output structure (confidence score, label, signals, seller profile, summary), discloses the meaning of 'assessable: false' and instructs how to handle it, and explicitly warns against misrepresenting unrun checks. This goes far beyond the annotation.

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 dense but every sentence adds value. It front-loads the core purpose, then moves to usage, output, and edge-case handling. No filler, no repetition of schema details, and the structure makes it easy to scan. The length is justified by 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 no output schema, so the description must explain return values and edge cases. It does so comprehensively: explains the verdict is about a specific sale, lists the returned fields, and details the 'assessable: false' scenario with instructions on how to report it. Combined with rich annotations and full schema coverage, the description completes the picture.

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?

With schema description coverage at 100%, the baseline is 3, but the description adds crucial semantic meaning: it designates 'label' as the primary parameter, clarifies that tx_hash, buyer, seller, and price_eth are optional enrichment, and explains that tx_hash is for pre-computed scores while others are for live analysis. This role differentiation and usage priority are not in the 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+resource: 'Assess whether an ENS name's sale(s) are WASH TRADING / fake / self-dealt / manipulated volume.' It explicitly distinguishes itself from siblings by stating 'do NOT use get_name_details or get_market_activity for that' because those tools make no wash-trading judgment. This clearly identifies the tool's unique role.

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 provides explicit when-to-use guidance: 'THE tool for any ... question — route straight here' and explicitly names alternatives that should not be used for this purpose. It also instructs on parameter usage: 'Just pass label... is enough' and states optional parameters 'never block on them or ask the user for them.' This is exemplary usage guidance.

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