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

With no annotations, the description fully discloses key behaviors: only HTTP 3xx handling, no JS execution, deterministic, returns hop chain, cross-origin flag, and cost. Missing details on rate limits or timeouts, but adequate.

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 informative but dense, mixing many details (EIP-191 receipt, cost) that could be separated. It is not front-loaded in a concise manner.

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 simple input schema and the detailed description of outputs (hop chain, final URL, canonical, etc.), the tool is well-described for its purpose. It also states limitations.

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 single parameter 'url' is fully covered by the schema description. The description adds no additional meaning beyond the schema, so 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 clearly states it resolves a URL and provides redirect chain, final URL, canonical link, and safety signals. It distinguishes from siblings like fetch or headers by focusing on redirect resolution.

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?

It explains the tool's behavior (follows HTTP 3xx only, no JS/meta-refresh) and mentions deterministic results. However, it does not explicitly tell when to use this tool versus alternatives like fetch or metadata.

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