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

The description significantly expands on the annotations by clarifying that the currency code is merely the issuer's declaration, not attested backing, and explicitly lists the inspected control mechanisms: seize/freeze/pause/uncapped-mint. It also discloses pricing, billing behavior via x-credit-token header, and that no wallet or API key is required, which is useful operational context beyond the readOnlyHint and idempotentHint 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?

The description is information-dense and front-loaded with the core purpose before moving to the caveat and payment details. It earns its length by explaining the non-attested nature and billing/trial terms, though a slight tightening around the payment sentence could make it even more scannable.

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?

For a single-parameter read-only tool with a rich output schema and strong annotations, the description covers the what, why, caveat, and invocation context. Nothing needed for correct tool selection or calling 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 coverage is 100% and the single address parameter already has a clear description ('B20 Stablecoin address'). The tool description only repeats 'Required input: address' without adding new format, validation, or example details, so it meets the 100%-coverage baseline but does not go beyond it.

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 clearly states a specific verb and resource: it 'Reads' the declared peg, issuance profile, and control powers of B20 Stablecoin tokens. It also frames the tool as a one-call profile, which separates it from granular siblings like b20_peg, b20_supply, and b20_control.

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?

It provides clear context: agents settling in B20 stablecoins should use this when they need a one-call 'what is this stablecoin and who controls it' summary. It does not explicitly name alternatives or exclusions, but the one-call framing implies when to reach for this aggregated view instead of separate endpoint calls.

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