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

The annotation destructiveHint: true already signals that this tool can have a destructive effect (de-authorization). The description adds the context about device approval being enabled, which is useful. However, it does not disclose additional behavioral details such as reversibility or immediate network impact, though the schema's parameter description partly covers the meaning of 'authorize' vs 'de-authorize'.

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 only two sentences, with the main action front-loaded. The first sentence states the purpose, and the second provides the REST endpoint. No unnecessary words or repetition; every part adds value and it is highly efficient.

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 two required parameters and no output schema, the description covers the core context: what it does, when it's relevant, and the API call. The only minor gap is the lack of any return value description, but since there is no output schema and the tool's effect is straightforward, this is a minor omission.

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 input schema already provides 100% coverage with clear descriptions for both parameters (deviceId and authorized). The tool description does not add extra meaning beyond the schema, so it does not exceed the baseline score of 3. The parameter descriptions are self-explanatory.

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 tool's function: 'Authorize or de-authorize a device' with a specific resource (device) and verb. It also adds the REST endpoint, reinforcing the exact action. This distinguishes it from sibling tools like tailscale_get_device or tailscale_delete_device, which perform different operations.

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 provides a clear usage condition: 'only relevant when device approval is enabled for the tailnet.' This tells the agent when this tool applies. While it doesn't explicitly exclude alternative tools, the tool's unique purpose and the relevance condition offer sufficient guidance for selection.

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