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

The only disclosed behavior is that 'Title discarded after the call.' With no annotations present, the description carries the full behavioral burden, yet it omits whether the tool is read-only, what it returns, whether it makes a network request, or how errors are reported. The discarding note is a small positive but far from sufficient.

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 extremely concise — two short sentences with no filler. The main purpose is front-loaded. It earns a high score for brevity, though it sacrifices completeness.

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?

This tool has a seven-property schema, no annotations, no output schema, and the description is only two sentences. It fails to specify which parameter to use, what the return value is, or any side effects. The definition is inadequate for an agent 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 description never explains which input parameter corresponds to the Wikipedia title. The schema exposes seven unrelated properties (ref, url, city, feed, host, json, path), none of which is a title, creating a serious mismatch. Even though each schema property has a description, those descriptions reference 'shape check' and do not map to the described purpose.

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 specific action: 'Check whether a Wikipedia title exists.' It names a distinct resource (Wikipedia title) and a clear verb, so an agent can tell it apart from siblings like domain-shape or url-shape. However, it does not explicitly differentiate from related 'shape' checkers, and the word 'exists' versus 'shape' could be ambiguous.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention any conditions, exclusions, or comparison to sibling tools. An agent must infer usage entirely from the tool name and one-line description.

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