opn_arp_table

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

No annotations are provided, so the description carries full burden. It discloses that the tool returns a dict with fields (ip, mac, intf, hostname). It does not describe side effects, authentication, or rate limits, but for a simple read-only tool with no parameters, this is acceptable. The description gives sufficient behavioral context for an agent to understand the output format, but could mention if the data is live or cached.

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 extremely concise: two sentences and a one-line output note. It is front-loaded with the core purpose, followed by usage scenarios and return format. Every word earns its place, with no unnecessary information.

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 the tool's simplicity (no parameters, no side effects) and the presence of an output schema, the description is complete. It explains the tool's function, when to use it, and the structure of the returned data. No gaps are apparent.

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?

The tool has zero parameters, and schema coverage is 100% (since no params exist). According to guidelines, baseline for 0 parameters is 4. The description adds no parameter-specific information because there are none, which 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 'Get the ARP table showing IP-to-MAC address mappings,' using a specific verb and resource. It distinguishes from sibling tools like opn_ndp_table (IPv6 NDP) by focusing on ARP table, which is IPv4-specific. The description provides a precise and unambiguous purpose.

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 explicitly states when to use the tool: 'when you need to find which MAC address is associated with an IP, identify devices on a network segment, or troubleshoot connectivity.' It does not explicitly mention when not to use or provide alternatives, but the context of sibling tools (e.g., opn_ndp_table for IPv6) provides implicit guidance. The usage guidance is clear and helpful but lacks explicit exclusions.

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