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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds a meaningful privacy-related guarantee ('Never exposes card details or secrets') that goes beyond 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?

Single sentence with no redundant wording. It efficiently conveys the purpose, scope, and a key safety guarantee.

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 that the tool has no parameters and has an output schema, the description sufficiently covers what the tool does, its scope, and the main reader concern (no secrets exposed). No additional context is needed.

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?

The tool has zero parameters and schema coverage is 100%, so there is nothing to describe. The baseline for zero parameters is 4, and the description appropriately focuses on the resource being read.

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?

Description clearly states the verb 'Read' and the resource 'authenticated user's Agent Buyer Wallet state, limits and readiness,' distinguishing it from sibling tools like agent_buyer_wallet_configure and agent_buyer_wallet_setup.

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 clearly indicates this is for reading wallet state, limits, and readiness, and adds the important negative guarantee that it never exposes card details or secrets. It does not explicitly name alternatives, but the read-only purpose is unmistakable.

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