vpn_client

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

Annotations mark it as a non-read-only, non-destructive, closed-world operation. The description adds valuable behavioral context beyond the annotations: `connect` blocks and waits for the tunnel, and the result reports whether the tunnel is up plus the assigned address. Per-action side effects are thus disclosed.

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?

One dense but well front-loaded sentence: the general purpose comes first, then the action-specific requirements, then the return value. No wasted sentences, though the parameter list makes it slightly heavy.

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?

With an output schema present and annotations covering the safety profile, the description need not expand on returns or permissions. It covers all three actions adequately; only the lack of explicit sibling routing keeps it from being fully complete.

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%, so every parameter is already documented in the schema (including the timeout default of 15 and max of 300). The description only groups which params apply to `connect`, matching the schema rather than adding new meaning, so the baseline 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?

States a specific verb and resource: using a device's VPN app against an Easy VPN server, with the three actions (connect/disconnect/status) named. It is clear what the tool does, though it does not explicitly distinguish itself from the sibling tools literally named `connect` and `disconnect`.

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 explains what each action does and that `connect` requires server, group, group_key, username and password, which implies when to call each. However, it gives no explicit guidance on when to choose this tool over siblings like `connect` or `connect_wireless`.

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