ping_instances

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

The readOnlyHint already covers safety, yet the description still adds real behavior: each answer is returned, and BunkerWeb replies 502 if any ping fails, which is important failure framing for a broadcast call. It stops short of saying whether slow or unreachable instances time out individually or how the aggregate response is shaped, so it is strong but not exhaustive.

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?

Two compact sentences: capability and scope first, failure behavior second, sibling disambiguation last. Every clause carries distinct information with 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?

For a single-optional-parameter read tool with annotations and no output schema, the description covers what it does, the default broadcast behavior, and the failure signal. The only gap is the shape of the returned 'each answer' payload, which matters somewhat for a fan-out call but is a minor omission here.

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% and the schema already states 'Hostname of one instance, as returned by list_instances; omit to ping every instance', which duplicates the description's parenthetical. The description adds no new syntax, format, or validation detail beyond the schema, so the baseline of 3 applies.

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?

A specific verb plus resource plus scope: 'Ping one instance (hostname) or every registered instance (hostname omitted) and return each answer.' It also names the sibling it is not (list_instances for registration data without pinging), so an agent can distinguish it without opening the schema.

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?

Explicit when-to-use is encoded in the parameter: pass a hostname for one instance, omit it to ping all. It explicitly routes the agent away from this tool when plain registration data is wanted: 'Use list_instances for registration data without pinging.' Nothing is left to inference.

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