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

With no annotations, the description carries the full burden. It does disclose two useful behavioral traits: the operation is a live network inspection, and it requires payment of 0.01 USDC via x402. It does not mention rate limits, failure modes, or auth beyond the payment hint, so it is adequate but incomplete.

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 compact sentence with the inspected checks front-loaded after the colon; every clause earns its place. The parenthetical cost is tucked in but does not obscure the primary purpose.

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 and no annotations, the description should ideally convey what the agent receives back, such as grade format or raw JSON. It names the inspection targets but leaves the return shape and payment flow mechanics underspecified for a paid recon tool.

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% and the single 'domain' parameter is fully documented in the schema, so the baseline is 3. The description adds only the target scope (DNS/TLS/security header OSINT), not format or syntax details beyond the schema.

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 pairs a specific verb ('Inspects') with a precisely enumerated resource set: live IPv4/IPv6 DNS resolution, TLS certificate issuer/expiry, and HTTP security grade. This clearly distinguishes it from adjacent siblings like enrich_company_domain and recon_webpage_skeleton, which operate at different scopes.

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 implied by the recon framing and the enumerated checks, so an agent can infer this is for a domain-level security/DNS audit. However, it offers no explicit when-to-use, when-not, or named alternative against the many sibling recon/enrichment tools.

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