list_tunnels

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

With no annotations provided, the description carries the full burden. It discloses key behavioral traits: it shows all tunnels in the registry, auto-detects running tunnels not in the registry, displays specific details (status, name, URLs, runtime info), and indicates local vs. remote. However, it lacks information on permissions, rate limits, or error handling, which are important for a tool with no annotations.

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 well-structured and appropriately sized. It starts with a clear purpose statement, uses bullet points for key behaviors, and ends with usage guidance. Every sentence adds value without redundancy, making it efficient and easy to parse.

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 complexity (listing and auto-detecting tunnels), no annotations, no output schema, and 0 parameters, the description is mostly complete. It covers purpose, usage, and behavioral details but could benefit from mentioning output format or error cases. However, it provides sufficient context for basic use.

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 has 0 parameters with 100% coverage, so no parameter documentation is needed. The description appropriately does not discuss parameters, focusing instead on the tool's behavior and output. Baseline for 0 parameters is 4, as it avoids unnecessary parameter details.

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 specific action ('Lists all active tunnels') and resource ('tunnels'), including their status and details. It distinguishes from siblings by focusing on listing/status checking rather than starting or stopping tunnels, which are the sibling tools.

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 explicitly states when to use this tool: 'Use this tool to check the status of your tunnels and get their public URLs.' This provides clear context for usage versus the sibling tools (start_tunnel, stop_tunnel), which are for different operations.

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