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

The description adds valuable behavioral context beyond the annotations: the operation is permanent, requires a one-time namespace_token, and costs $0.005 USDC on Base via x402. This aligns with the destructiveHint=true annotation without contradicting it. The irreversibility warning is genuinely useful for an agent, though the description could have expanded on the payment failure behavior.

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?

Two concise, information-dense sentences. The permanent, destructive nature is front-loaded, followed by the required token and cost. Every word contributes value and there is no redundancy.

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 the destructive annotation, idempotent hint, and 100% schema coverage, the description covers the essential operational details: irreversibility, required token, and cost. A small gap is the lack of detail about the x402 payment flow or failure consequences, but the current information is sufficient for an agent to invoke correctly.

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 fully documents all three parameters. The description does not add additional semantic detail beyond what the schema provides, so the baseline score of 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 clear verb and resource: 'Permanently delete an item.' The title clarifies it deletes a stored secret, which distinguishes it from sibling tools like vault_retrieve and vault_list. However, it doesn't explicitly name the sibling it is not, so it relies on the delete semantics for 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?

The description identifies a key prerequisite ('Requires the namespace_token') and a practical cost consideration, both useful for deciding whether to invoke. It doesn't explicitly state when not to use it or name alternatives, but the destructive nature and token requirement provide clear usage context.

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