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

With no annotations, the description carries the full burden, and it does disclose a useful behavioral trait: query and fragment are dropped while origin, host, and path are returned. However, it does not explain how the other schema parameters (host, json, zone) behave, what happens with invalid URLs, or whether there are side effects. This leaves the agent with only partial transparency about the tool's actual surface.

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?

Two short sentences with no filler, and the primary behavior is front-loaded. The brevity is effective for the described operation, though it is achieved by omitting any mention of the three additional schema parameters.

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 description covers the URL-normalization use case well, but the schema accepts three additional parameters (host, json, zone) that are not addressed at all. With no output schema and no annotations, an agent cannot determine whether these parameters alter behavior, are ignored, or represent separate functions. This is a significant completeness gap for a 4-parameter 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?

Schema coverage is 100%, so the baseline is 3. The description adds meaning for the url parameter by specifying the extracted output components (origin, host, path) and the dropped components (query, fragment). However, it says nothing about the host, json, and zone parameters, leaving their role in the operation ambiguous.

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 states a clear operation: return origin, host, and path for a URL, and explicitly notes that query and fragment are dropped. This is a specific verb plus resource, easily distinguished from unrelated siblings like generate_password or get_weather. However, it does not differentiate from close URL-related siblings such as scrape_url, open_url, or add_port, and the schema's unrelated parameters are left unexplained.

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 provides no guidance on when to use this tool versus alternatives. Sibling tools like scrape_url, open_url, add_port, and query_builder exist, but no conditions, exclusions, or alternative names are mentioned. The only implicit signal is the tool name and URL-normalization behavior.

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