tailscale_list_services

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

Annotations already indicate readOnlyHint=true, destructiveHint=false, and idempotentHint=true. The description adds valuable context about service lifecycle (implicit creation, no create endpoint) that is not in annotations, enhancing transparency beyond structured metadata.

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 two sentences plus a note, front-loading the core purpose. Every sentence serves a distinct role: statement of function, explanation of creation mechanism, and guidance on related tools. No superfluous content.

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?

Given the tool's simplicity (list all, no params) and lack of output schema, the description covers the essential usage. However, it does not describe the return format or fields, which could aid an agent in downstream processing. Still, the core action is fully specified.

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 has zero parameters. The description does not need to add parameter meaning because there are none. The schema coverage is 100% (empty schema), and the description correctly implies no input is needed.

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 it lists all Tailscale Services in the tailnet. The verb 'List' and resource 'Tailscale Services' are specific. It distinguishes itself from sibling list tools (e.g., list_devices, list_keys) by naming a different resource type.

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?

Explicitly notes that services are created implicitly via `tailscale up` and that there is no API to create them via this MCP. It directs users to use update/delete/approval tools once the service exists, providing clear when-to-use and when-not-to-use guidance.

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