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

Annotations already declare readOnlyHint/idempotentHint, and the description reinforces this with the crucial disclosure that the MCP does NOT build or broadcast the payment and that signing happens in the user's wallet on the website. That is exactly the kind of context annotations cannot convey. It stops short of stating link expiry or reuse behavior.

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?

Three compact sentences: purpose and accepted TLDs first, the critical browser/wallet caveat second, the trigger phrases and refcode rule last. No sentence is redundant.

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?

With no output schema, the description carries the return-value burden and does so by stating the tool returns a link and that the transaction completes externally. 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 coverage is 100%, so both parameters are already documented, establishing a baseline of 3. The description adds a real usage condition for refcode ('Pass refcode if a referral applies') that the schema's terse 'optional referral code' does not, lifting it slightly above baseline.

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?

States a specific verb (get the link to register) and a concrete resource (a .xrp/.xrpl/.xrpfi/.rlusd domain on xrpdomains.xyz), and makes clear it is not the registration itself. This cleanly separates it from siblings like check_domains, recommend_domain, and get_domain_profile.

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?

Gives explicit trigger phrases ('register X.xrpfi', 'buy X.xrp') and a conditional rule for refcode. It does not name alternatives such as check_domains for availability or recommend_domain for name suggestions, so the when-not path is left implicit.

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