ssh_tunnel_close

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

With no annotations provided, the description carries the full behavioral burden, and it does so thoroughly. It discloses that the operation is irreversible ('Closing is final and cannot be undone'), scoped to local state only, and that the server mode reports how many tunnels were closed.

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 dense sentences convey the action, scope, parameter contract, error behavior, and irreversibility without any filler. The most important scoping information is 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 two-parameter tool with no output schema and no annotations, the description is complete enough to invoke correctly: it explains what each parameter does, the exclusivity constraint, the error case, the local-only effect, and the destructive finality. An agent has sufficient information to decide when and how to call this tool.

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?

Although the schema already describes both parameters, the description adds critical semantics beyond the schema: the exact-one requirement, the difference between single-tunnel and server-wide closing, and the error condition when neither is supplied. This meaningfully helps an agent choose and populate the right parameter.

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 names a specific action ('Tears down active SSH tunnels') and a clear resource ('active SSH tunnels created earlier'), and immediately clarifies scope by saying it affects only local tunnel state and not the remote host. This distinguishes the tool from related SSH tools like ssh_tunnel_create and ssh_session_close without ambiguity.

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 explicit parameter-selection rules: exactly one of tunnelId or server must be supplied, tunnelId targets one tunnel, server targets all tunnels for that server, and supplying neither raises an error. It provides clear operational context, though it does not explicitly name alternatives such as ssh_tunnel_list for discovering tunnel IDs.

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