vps_list_banned_ips

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

The description says 'Read-only', which aligns with the readOnlyHint annotation. It adds 'currently banned' indicating a snapshot view. However, it does not disclose error behavior (e.g., what if jail doesn't exist) or output format. Since annotations already cover read-only and idempotent, the description adds minimal extra behavioral context.

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?

The description is a single sentence, front-loaded with the action, and has zero waste. It conveys the core functionality and the key parameter in a compact form, making it easy for an agent to parse quickly.

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 tool with one optional parameter and no output schema, the description covers the essential aspects: what it does, the jail parameter and its default, and read-only nature. It does not describe output format or error handling, but these are less critical given the tool's simplicity and the annotations. It is mostly complete for an agent to invoke correctly.

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 0%, so the description must compensate. It explains that 'jail' is the fail2ban jail and provides a default ('sshd'), giving meaning beyond the bare type. However, it does not describe possible values, whether it's optional (though default implies it), or any constraints. It covers the parameter's purpose adequately but not exhaustively.

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 clearly states the verb 'List' and the resource 'IP addresses currently banned by fail2ban', with the jail parameter. This distinguishes it from siblings like vps_unban_ip (which removes bans) and vps_status (which shows status). No ambiguity about what the tool does.

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 mentions a default jail ('sshd') but does not explicitly state when to use this tool versus alternatives like vps_unban_ip. It is implied that this is for checking banned IPs, but no explicit when/when-not guidance is provided. The read-only annotation offers some context, but the description itself lacks direct routing instructions.

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