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

Annotations already declare readOnlyHint/openWorldHint/idempotentHint/destructiveHint, so the safety profile is covered. The description adds genuinely new operational context that annotations cannot carry: the $0.02 x402-on-Base pricing, the prepaid x-credit-token header for unlimited calls, no free tier, and no API key required, all of which materially affect invocation.

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 core purpose is front-loaded before the payment/auth logistics. It is slightly dense with em-dash clauses and commercial detail, but every sentence carries information an agent needs, so little is wasted.

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?

An output schema exists, so return-value explanation is unnecessary, and annotations carry the safety profile; the description covers pricing and auth. The one notable omission is which chains the approval scan covers, which for a cross-chain sibling set would be useful context.

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 there is a single required parameter. The description only restates 'Required input: address,' adding no syntax, format, or chain-scoping detail beyond what the schema already declares, so the baseline of 3 applies.

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 and resource ('lists a wallet's active token approvals') and enumerates the returned data (spendable contracts, allowance, USD at risk, risk factor), which is highly concrete. It does not explicitly name or differentiate itself from closely related siblings such as approval_advisor or revoke_builder, so it falls short of full sibling differentiation.

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?

'Essential wallet-security check for agents and users' implies a usage context but gives no explicit when-to-use/when-not guidance. It never names the alternatives (approval_advisor, revoke_builder, safe_approve) that would let an agent route correctly among the many approval-related siblings.

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