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

With no annotations, the description carries the full burden and does so well: it discloses the exact cost per chain (0.1 XRP / 0.05 USDC), the required credential artifacts, the facilitator's decode-and-bind behavior, and the precedence rule that x_sol_payload causes XRPL args to be ignored. This is behavior an agent could not infer from the schema.

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?

Purpose and payment requirement are front-loaded, then a structured Args block maps cleanly to the parameters. Slightly dense with per-chain formatting, but every line adds decision-relevant information.

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 paid, 4-param tool with no annotations and no output schema, the description covers the gating requirements thoroughly. It does not describe what the returned field schema looks like or its format, which is the only notable gap.

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 0%, so the description must compensate, and it does: slug gets a concrete example, x_payment_signature is defined as a JSON string containing tx_hash and signedTxBlob (both required), x_inv_id is identified, and x_sol_payload is marked OPTIONAL with its encoding and effect.

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 the resource precisely ('Field schema for one country') and flags the payment requirement, which distinguishes it from the free-data siblings like xrplme_get_country_data. The verb is implicit (return/fetch) rather than stated, and it never explicitly contrasts itself with the other country tools.

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?

Usage is only implied: it tells you the tool costs money and how to pay, but not when to choose it over xrplme_get_country_data or xrplme_get_country_status. The rich payment guidance describes the mechanism, not the selection condition.

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