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

Annotations indicate openWorldHint=true, and the description confirms side effects by exposing a server. It adds that the tool uses ngsrv and returns values, but does not disclose prerequisites (e.g., needing a token) or potential limitations like tunnel duration.

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 three concise sentences, front-loading the core action and output, followed by use cases and a follow-up suggestion. No wasted words.

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 simple single-parameter tool and annotations, the description is reasonably complete: it covers the action, output, and use cases. It lacks error handling or prerequisites but is sufficient for basic operation.

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% with a detailed description and examples for the port parameter. The tool description does not add additional meaning beyond the schema, so it meets the baseline for high coverage.

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 exposes a local HTTP server on a public URL via ngsrv and returns specific fields. It distinguishes from sibling tools like tunnel.list and tunnel.stop by mentioning use cases and suggesting a follow-up.

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 explicit use cases (webhooks, OAuth callbacks, sharing dev servers) and suggests using tunnel.list afterward, giving clear context. However, it does not explicitly state when not to use this tool.

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