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

Annotations already declare idempotent and non-destructive behavior, so the description need not restate safety. It does add a genuine behavioral fact beyond the structured fields: the call costs $0.01 USDC, signaling a paid operation. It does not explain the readOnlyHint=false or what the returned score means.

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?

A single terse line with no filler, and the core purpose is front-loaded before the pricing detail. Appropriately sized for a one-parameter lookup, though it verges on under-specification.

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 minimal one-param, no-output-schema tool, the description conveys what is returned (a trustworthiness score) and the cost of the call. The main missing piece is guidance on output shape or failure modes, but the low complexity keeps this adequate.

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 0% and the single required parameter (endpoint_url) carries no description, so the description must compensate. 'Endpoint trustworthiness' clarifies that the parameter is the endpoint being scored, which adds meaning, but it omits format expectations (URL scheme, host only, etc.).

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 names a specific resource ('agent reputation score' for 'endpoint trustworthiness'), making the tool's function clear. It implicitly distinguishes itself from sibling risk tools like wallet-risk and token-safety by scoping to endpoint trust. A retrieval verb is only implied, but the resource is unambiguous.

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?

There is no guidance on when to use this tool versus alternatives such as wallet-risk, token-safety, or sanctions-screen, which occupy adjacent trust/risk domains. The only usage-relevant fact disclosed is the per-call price.

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