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

Annotations already declare the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower. The description adds useful context: the scoring inputs, the 0-100 trust score output, trust level, and ERC-8004 compatibility. It does not add auth/rate-limit or data-freshness details, keeping it short of a 5.

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?

Purpose is front-loaded, followed by use case, then scope exclusions. The final negation sentence packs three exclusions but remains parseable. Slightly dense, though every clause carries routing value.

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?

With an output schema present, the description needn't explain return structure; it still mentions outputs briefly. Annotations cover safety, schema covers params, and the description covers purpose, inputs, and sibling disambiguation. Nothing an agent needs to invoke it correctly is missing.

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% and the chain enum with its default is fully documented in the schema, so the baseline is 3. The description adds no addressing or chain-selection nuance beyond what the structured fields already carry.

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?

States a specific verb+resource ('KYA: 10-factor on-chain reputation scoring') and enumerates the exact factors evaluated. It explicitly names the siblings it is not (wallet.credit_score, agent.card.lookup), so an agent can distinguish it without opening any 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?

Gives an explicit trigger ('Use this before relying on another Agent') and negative routing with named alternatives ('It is not a wallet's financial activity score (wallet.credit_score), a registered identity card (agent.card.lookup)'). When-to-use and when-not-to-use are both spelled out.

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