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

With no annotations provided, the description carries the full burden and does well: it discloses hop-by-hop traversal, status code reporting, final destination, and the cross-host flag. It stops short of mentioning error handling or timeouts, but covers the core observable behavior effectively.

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 sentences, front-loaded with the core action and output, followed by use cases and a notable behavior flag. Every sentence adds value, with no redundancy or filler.

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?

The tool is relatively simple, and the description covers its primary behavior, use cases, and a safety-relevant flag (cross-host change). No output schema exists, but the description tells the agent what to expect. Minor gaps like response format details or failure modes prevent a perfect score.

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%, and both parameters (url with default scheme, maxHops with range) are already well-described in the schema. The description adds no additional parameter meaning ('maxHops' is not mentioned in the description), so a baseline 3 is appropriate.

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 uses a specific verb ('Follow') with a clear resource ('URL's redirect chain') and states the exact output ('report every stop with its status code, plus the final destination'). It clearly distinguishes this tool from sibling network diagnostics (dns_lookup, ping, check_service_status) by focusing on redirect chain traversal.

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 lists three concrete use cases: investigating shortened/tracking links, debugging redirect loops, and verifying migration redirects. It does not mention when NOT to use the tool or name alternative tools, so it misses the 'exclusion' part of a 5-level score.

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