hijack_dangling_mx

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains the detection mechanism (NXDOMAIN check) and the consequence, which gives a transparent view of what the tool does internally. It doesn't cover return format or limitations, but the core behavior is well-described.

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 concise sentences that front-load the purpose and then provide context. Every word contributes value, with no redundancy or ambiguity.

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 tool with a single parameter and no output schema, the description provides a clear understanding of the tool's purpose and detection logic. It lacks details about the output format or example results, but given the simplicity, it is reasonably complete and sufficient for an AI agent to select and invoke correctly.

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 coverage is 100%, so the baseline is 3. The description adds meaning beyond the schema by explaining what 'dangling' means in the context of MX records and how the domain parameter relates to the detection process. This supplements the schema's simple parameter description.

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 the tool detects dangling MX records that could allow email hijacking, using the specific verb 'Detect' and identifying the resource (MX records). This distinguishes it from sibling tools like hijack_dangling_cname and hijack_dangling_ns.

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 explains the precise condition under which the tool is relevant: if an MX hostname resolves to NXDOMAIN, an attacker can register it. This gives clear context for when to use the tool, though it doesn't explicitly mention alternatives or exclusions. The condition implies the tool is for checking MX-specific dangling records.

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