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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=true and destructiveHint=false, so safety is covered. With no output schema, the description carries the return-shape burden and does well: it says results repeat each party's own terms with a link and a date, include on-chain mint/freeze authority readings, and explicitly say what is not established. It also warns that it records who *can* use a power, not whether they will — a useful interpretive caveat. Failure modes and coverage gaps are still unaddressed.

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 response shape is front-loaded ("which company or group holds which of nine powers over a coin") before the enumerated powers and caveats. It is dense but every clause carries information, particularly the enumeration of return fields that no output schema supplies.

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 lookup with no output schema, the description supplies the return contents, the accepted query forms, the epistemic limits of the result, and the interpretive caveat about capability versus intent. Nothing essential for correct invocation 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 single query parameter is already documented as accepting a coin, company, or question with the same examples the description gives. The description adds little beyond the schema here, so the baseline 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 and unusual resource: which party holds which of nine named powers (freeze, pause, mint, redeem, custody, govern, validate, pay out, bridge) over a coin. Its scope is unique among the siblings (coin_profile, exit_cost, exit_index, explain_transaction, identify_address, search), so an agent can tell it apart implicitly, though no sibling is named explicitly.

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 gives clear trigger contexts: questions about a coin ("USDC"), a company ("Circle"), or a class of coins ("which stablecoins can be frozen"). That is enough to know when to reach for it, but there are no exclusions or explicit hand-offs to sibling tools such as coin_profile.

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