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

The description discloses critical behavioral traits beyond annotations: 'SENDS REAL TRAFFIC to the target and may trigger intrusion detection,' the cost of $3, and the async option. These significantly inform the agent about real-world impact, which annotations only partially cover.

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 three sentences long, front-loaded with purpose, and every sentence adds value: purpose, safety warning, and async/cost. No redundant words; all information is necessary.

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?

Given no output schema and moderate complexity, the description covers purpose, authorization, real-traffic warning, cost, and async behavior. However, it omits details on scan_type semantics and port_range, which are needed for smooth invocation. This is a notable but not fatal gap.

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 only 20%, so the description carries more burden. It clarifies target as 'IP or domain' and async as returning a job_id, but leaves required scan_type enum values (quick/standard/deep) and port_range format unexplained. The description adds some meaning but does not fully compensate for the low coverage.

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 'Discover open ports, running services and known vulnerabilities on an IP or domain (nmap),' providing a specific verb and resource. The parenthetical '(nmap)' distinguishes it from siblings like vuln_scan_web_app, making the tool's scope immediately clear.

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?

It provides explicit authorization guidance: 'only run against hosts the caller owns or is explicitly authorized to test, and confirm that first.' It also mentions async usage for non-blocking execution, but does not explicitly contrast against alternative tools like vuln_scan_web_app, though this is implied by 'nmap'.

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