arp_table

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

With no annotations the description carries the full burden, and it does well: it discloses the non-obvious behavioral fact that a device only gets an ARP entry after exchanging traffic. It does not state read-only nature explicitly (implied by 'List') nor pagination, so not a 5.

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?

Front-loads the resource and column list, then the usage rationale. The parenthetical aside is slightly verbose but each sentence carries signal; no filler.

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?

Output schema exists, so return values need not be explained, and the description still enumerates expected columns. For a one-param read tool with no annotations, the guidance on when it beats dhcp_leases makes it essentially complete.

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?

One required parameter (device_name) with 0% schema description coverage. The description does not explain the device_name parameter at all, leaving the agent to infer it targets a specific device. Baseline is 4 for zero-param tools, but here the single param is unexplained, so 3.

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?

States a specific verb and resource ('List the IPv4 ARP table (/ip/arp)') and even enumerates the returned columns. The explicit '/ip/arp' path and IPv4 qualifier distinguish it from ipv6_neighbors and ip_addresses.

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?

Gives an explicit when-to-use scenario: cross-referencing IP to MAC for a statically-addressed device that will never appear in dhcp_leases. Naming the sibling dhcp_leases and the exclusion condition is exactly the routing guidance an agent needs.

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