tunnel_list

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, lowering the bar. The description nonetheless adds non-obvious behavior: secret values are never included in the output, and it specifies the exact return line format and the empty-list literal.

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?

Front-loaded with purpose and usage before the format details; every sentence carries information. The standalone 'Read-only.' sentence duplicates the readOnlyHint annotation, a minor redundancy that keeps it out of the top band.

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?

There is no output schema, so the description correctly supplies the return shape and the empty-case behavior. For a zero-parameter, read-only listing tool this covers everything an agent needs to call and parse it.

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 takes zero parameters, so the baseline of 4 applies; there is no parameter syntax left for the description to compensate for.

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?

States a specific verb and resource (enumerate active tunnels in the q-ring server) plus the exact payload returned (remaining read budget and TTL). It is clearly distinguishable from siblings tunnel_create, tunnel_read, and tunnel_destroy by naming its enumeration/audit role.

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?

Gives two concrete use cases: auditing what is still in memory and recovering a forgotten tunnel ID. It does not explicitly name an alternative tool or state when not to use it, so it falls short of the top band.

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