Tunnel status

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context by naming the output details (public URL, uptime, state, last error) and clarifying this tool only inspects a single tunnel, not the entire set.

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 with no filler. The primary function and output are front-loaded in the first sentence, and the sibling guidance is compactly placed in the second. Every word contributes value.

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 simple read-only tool with complete schema coverage and annotations, the description covers the core operation, output fields, and sibling differentiation. However, it does not explicitly state that port or label must be provided, and the schema lists no required parameters, leaving a small ambiguity for an agent calling with no arguments.

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 100%, with clear definitions for port and label, so the baseline is 3. The description adds the relationship that these are alternative identifiers ('local port or its link label'), but it does not provide material meaning beyond the schema.

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 uses a specific verb ('Return'), names the resource ('a single tunnel'), and specifies its identifier ('local port or its link label'). It also lists the returned data fields, making the tool's function unambiguous and distinct from list_tunnels.

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 second sentence explicitly tells the agent when to prefer a sibling tool: 'To see every active tunnel at once, use list_tunnels instead.' This directly states the condition for using the alternative, which is exactly the kind of guidance needed for correct tool selection.

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