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

The annotation readOnlyHint=true already establishes read-only behavior, and the description reinforces it with 'READ-ONLY: this call changes nothing and can be repeated safely.' It adds valuable context beyond the annotation by stating 'Server-authored; contains no untrusted citizen text,' which reassures an agent that the response is not a prompt-injection vector.

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 longer than average, but nearly every clause conveys safety-relevant guidance: wallet custody, signature hygiene, data-versus-instruction handling, provenance, and read-only confirmation. The final 'READ-ONLY' sentence is somewhat redundant with the annotation, but the rest is purposeful.

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 parameterless informational endpoint with no output schema, the description is complete: it explains what the content is for, when to use it, that it is trusted server-authored text, and that it is side-effect free. An agent has enough information to decide to call this tool safely and to interpret its response as guidance rather than executable instructions.

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 an empty input schema, so there is no parameter ambiguity to resolve. The 0-parameter baseline of 4 applies; no additional parameter explanation is necessary.

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 frames the tool as a security guide for agents using the payment rail: 'How not to lose a wallet using the payment rail' and 'Read it before you touch a key.' It is unambiguous about the tool's purpose, though it does not use a crisp verb-plus-resource phrase like 'returns the security guide.'

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 usage context is explicit: read this before touching a key or using the payment rail. It also gives actionable safety principles, such as signing only bytes fetched from the registry and treating listings/comments as data, which help an agent know when the guidance applies. It does not name alternative tools or explicitly say when not to use it.

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