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 disclose useful traits beyond the schema: ICMP is unavailable from a hosted server, so TCP timing is used, and each call costs 1 credit. It does not cover failure/timeout behavior, what happens on an unresolvable host, or any rate limits beyond the credit cost, leaving real gaps for a network diagnostic.

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?

Three tight sentences with no filler; the measurement capability is front-loaded, and the cost note is placed last where it belongs. Every sentence carries information, though the redundant port-default mention is a minor waste.

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 3-parameter tool with no output schema and no annotations, the description covers purpose, mechanism, and cost but omits parameter semantics for count and any error or failure behavior. An agent could call it, but would be guessing about probe count and response shape.

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 0%, so the description must compensate, and it largely does not. The only parameter detail given is the default port 443, which simply restates the schema default. Neither 'count' (number of probes) nor the expected host format (domain vs IP vs host:port) is explained anywhere, leaving two of three parameters underspecified.

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 with measurable outputs: 'Measure round-trip latency, jitter and packet loss to a host by timing TCP connections.' It also explains the mechanism (TCP instead of ICMP), which pins down what the tool actually does. It stops short of distinguishing itself from close siblings like port_check or traceroute, so it earns a 4 rather than a 5.

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 gives an implicit use case ('checks that a service is reachable and how fast'), which points an agent toward reachability/latency checks. However, it never says when to prefer this over port_check, traceroute, or check_urls, nor when it is inappropriate. Usage is implied rather than stated.

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