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

With no annotations, the description carries the transparency burden. It discloses cost, payment method, and wallet linkage, which is valuable. However, it does not mention side effects like DNS changes for custom domains, potential name conflicts, or that omitting payment returns instructions. It is more transparent than a bare 'Create inbox' but still leaves out key behavioral details.

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 two sentences, front-loaded with the core action, and every sentence earns its place—first the what, then the cost/payment. There is no fluff or repetition of schema fields.

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 covers the primary purpose and cost, but given the tool's complexity (5 parameters, payment flow, no output schema, no annotations), it omits important operational details like the two-step payment flow (omit payment to receive instructions) and domain prerequisites (must be Namecheap-registered). The schema covers some of this, but the description itself leaves gaps for an agent deciding whether to invoke it.

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?

Input schema description coverage is high (80%), so the schema already explains most parameters. The tool description adds cost context and renames the address pattern, but it does not provide additional parameter-level meaning beyond what the schema offers. Baseline 3 is appropriate.

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 states a specific action ('Provision an email inbox') with a concrete resource format ('{name}@palmyr.ai or a custom domain you own'). It distinguishes itself from sibling tools like email_create_temp by implying a permanent, wallet-keyed inbox rather than a temporary one.

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 gives clear context for use: it costs 2.00 USDC, is paid per-action via x402, and is keyed to a wallet. It does not explicitly exclude alternatives or name sibling tools, but it provides enough context for an agent to understand when this tool is appropriate for provisioning a persistent inbox.

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