Verify the fetchproxy bridge end-to-end

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

The annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is known. The description adds valuable behavioral context beyond that: it explains the round-trip mechanism, lists the specific diagnostics returned (role, port, version, extension link, elapsed time, plain-English hint), and notes 'no auth required.' It also clarifies the failure-mode distinctions, which is useful for interpreting results. This goes beyond the annotations without contradicting them.

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 a single, well-structured paragraph that front-loads the core action and then enumerates the diagnostic outputs. The first sentence establishes the purpose and the second gives the usage scenario. Every sentence adds meaningful information without redundancy. It is dense but not bloated, making it an efficient and effective description.

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 parameterless healthcheck tool with no output schema, the description provides all necessary context: it states what it does, what it returns (including a list of specific diagnostics), when to call it, and its safety (read-only, no auth). The plain-English hint distinction further clarifies possible outcomes. Nothing essential is missing for an agent to decide when and how to invoke it correctly.

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, so the baseline is 4 per the instructions. The empty input schema is fully covered (100%), and the description doesn't need to explain parameters. Since there are no parameters to describe, this dimension is inherently satisfied at the baseline level.

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 a specific action: 'Round-trips a small public www.homes.com URL (/robots.txt) through the fetchproxy bridge and returns diagnostics.' It specifies the exact resource and the diagnostic purpose, which distinguishes it from the property search, mortgage, and other home-related siblings. The verb 'round-trips' and the diagnostic focus make its function unmistakable.

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 call: 'Call this when a real tool fails and you want to know which hop broke.' This gives a clear context for use. It does not, however, mention when not to use it or name specific alternative tools, but the sibling list makes it obvious this is for troubleshooting rather than normal operations. The absence of explicit alternatives is a minor gap, so a 4 is appropriate.

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