Check proxy health and diagnostics (preflight)

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

With no annotations, the description carries full burden. It thoroughly discloses the tool's behavior: 'Always returns' a specific list of fields, and conditionally returns additional fields 'While the proxy is stopped.' This transparently explains the state-dependent behavior and that it is a read-only diagnostic.

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 concise and front-loaded with 'Full preflight/diagnostics.' It efficiently lists the return fields and conditional behavior in two sentences without unnecessary fluff, earning every sentence's place.

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?

Despite having no output schema, the description thoroughly enumerates all return values and their conditional presence. It also includes usage guidance, making it a complete and self-contained description for a simple, parameterless tool.

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 has zero parameters and schema coverage is trivially 100%. Baseline for zero parameters is 4. The description adds meaning by explaining what the tool returns rather than parameters, which is appropriate since there are none to document.

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 purpose: 'Full preflight/diagnostics' for proxy health. It distinguishes itself from siblings by emphasizing this is the initial check to run, and the title 'Check proxy health and diagnostics (preflight)' reinforces the specific verb and resource.

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 says 'Use this first — it tells you everything needed to get running without shelling out.' This provides a clear when-to-use directive, positioning it as the preflight step before starting the proxy. It does not name alternatives or explicitly say when not to use, but the guidance is strong.

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