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

With no annotations, the description must carry the full behavioral burden. It discloses that query and fragment are dropped, which is useful, but it completely ignores the other eight parameters defined in the schema, leaving their behavior undisclosed. The description implies the tool only processes URLs, yet the schema suggests it accepts many other inputs, creating ambiguity about what happens when those are provided.

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, focused sentence with no wasted words. It front-loads the core purpose and includes a key behavioral detail. It is appropriately concise for the stated functionality.

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 has 9 parameters but the description only addresses one. There is no output schema, so the agent has no idea what the return format is beyond the vague 'origin, host, and path.' The mismatch between the narrow description and the broad schema makes the definition incomplete for an agent trying to decide whether to use it and how to interpret results.

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 description coverage is 100%, so each parameter is already described. The tool description adds nothing about parameters beyond mentioning 'URL' and the fact that query/fragment are dropped, which is already implied by the schema. This meets the baseline of 3 for high coverage.

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: 'Return origin, host, and path for a URL.' It is unambiguous about the primary function. However, it does not differentiate from sibling tools like browser-url-ok or figma-url-shape, which might also deal with URLs, so it misses the opportunity to disambiguate.

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. It only states what it does and that query/fragment are dropped, which is behavioral rather than contextual. There is no mention of exclusions, prerequisites, or comparisons to other tools.

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