domain_security_check

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

With no annotations, the description carries the full behavioral burden. It usefully discloses the paid nature (0.05 USDC on Base via x402) and the graded finding output, but it never states read-only status, whether the call mutates anything, or any rate/auth constraints.

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?

A single dense but front-loaded sentence that leads with the value proposition ('Security posture of a domain in one call') before enumerating coverage. No filler, though the comma-heavy list is somewhat dense.

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?

No output schema exists, so the description must carry the return contract, and it does by specifying the A-F grade, prioritised findings, and the full menu of checks. For a read-style posture tool this is nearly complete; only permission/auth and read-only confirmation are unstated.

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 fully documents both parameters (bare domain format, confirmNewPurchase semantics). The description adds no parameter-level meaning beyond what the schema already provides; baseline 3 applies.

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?

A specific verb+resource ('security posture of a domain') with an exhaustive enumeration of the checks performed (TLS, redirect, headers, SPF/DMARC, CAA, DNSSEC, RDAP, leak exposure) and the output shape (graded A-F). It clearly conveys what the tool does, but it never distinguishes itself from closely related siblings like trust_check, exposure_check, whois, or domain_tech.

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 never states when to reach for this tool versus the many overlapping siblings (trust_check, exposure_check, whois, domain_tech). The only usage-adjacent text is the cost note and the schema's purchase-confirmation guidance, neither of which routes the agent between alternatives.

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