Expire a device's key to revoke its current access and force it to re-authenticate, securing your tailnet against unauthorized use.
Expire a device's key, forcing it to re-authenticate.
| Name | Required | Description | Default |
|---|---|---|---|
| deviceId | Yes | The device ID to expire |
Changes observed during successful MCP inspections.
v0.13.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark this as destructive and idempotent. The description adds the context that the device will be forced to re-authenticate, but does not elaborate on side effects like immediate disconnection or notification behavior. It adds some value beyond annotations but lacks full transparency.
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, clear sentence that front-loads the action and effect with no extraneous words, achieving maximum conciseness.
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 (one parameter, no output schema, no complex logic), the description adequately covers the core action and consequence. However, some additional context about idempotency or call sequencing could enhance completeness.
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 coverage is 100% and the schema already describes the deviceId parameter. The description does not add any additional meaning or constraints beyond what the schema provides, resulting in no extra value for parameter understanding.
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 indicates the action ('expire') and the resource ('a device's key'), specifying the effect of forcing re-authentication. This distinguishes it from sibling tools like tailscale_update_device_key or tailscale_deauthorize_device.
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?
No guidance is provided on when to use this tool versus alternatives such as tailscale_authorize_device or tailscale_update_device_key. There is no mention of prerequisites, post-conditions, or scenarios where this tool is inappropriate.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.