peers

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 the key trait: results are a live snapshot of currently-online agents, not a persistent roster, and the caller's own address is always included. It does not state whether the call is strictly read-only or how discovery is performed (broadcast, cache, timeout), which would matter for a network-probing call, so it falls short of fully self-documenting.

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 sentences, no filler: the first defines the output, the second routes the agent. The most decision-relevant content (what you get, when to use it, where to go instead) is all front-loaded.

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 zero-parameter tool with no output schema, the description supplies exactly what is missing elsewhere: the return format (name@host addresses), the inclusion of the caller's own address, and the boundary against the sibling tool. Nothing an agent needs to call it correctly is absent.

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 takes zero parameters, so there is no parameter meaning to add; the baseline applies. The description correctly implies no filtering or scoping options exist by framing the result as an unfiltered list of everything online.

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 agents online now') and immediately defines the shape of the result: name@host addresses across this machine and others in the network, plus your own address. It is clearly separable from the sibling 'network', which it explicitly names as covering a different resource.

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 a direct when-to-use rule ('Use this to find who to send to') and an explicit exclusion routing to the alternative ('For the machines themselves, including offline ones and why, use network'). The agent needs no inference to choose between the two.

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