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

With no annotations, the description carries the behavioral burden. The verb 'Calculate' strongly suggests a non-mutating read-only operation, but the description does not explicitly state that no registration or bridging transaction is triggered, nor does it mention permissions, rate limits, or whether funds are moved.

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?

One sentence, front-loaded with the core action and outputs, with no filler or repetition of the tool name. Every part contributes to understanding what the tool does.

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?

The description identifies the main cost components but does not explain the return structure, units, or whether the result is a combined total or per-network breakdown. Since there is no output schema and no annotations, this gap leaves the agent without a complete picture of the response.

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%, so the schema already documents domainName and targetChainId, including the valid network IDs. The description's mention of '4 supported networks' adds minimal context but no parameter-level detail beyond what the schema provides.

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 uses a specific verb ('Calculate') and names concrete outputs (registration fee, escrow payment requirements, CCIP bridging costs) plus the scope (4 supported networks). This clearly distinguishes it from register_domain or bridge_domain, which actually perform actions rather than estimate costs.

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 description implies a pre-registration or pre-bridging cost-estimation use case, but it never explicitly says when to use this tool versus register_domain or bridge_domain, nor does it state when not to use it. The usage context is inferable but not spelled out.

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