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

The sentence 'Title discarded after the call' adds a privacy/retention trait beyond the plain 'check' wording. However, with no annotations present, the description still omits obvious behavioral details such as whether the call is read-only, what the result shape is, and how errors are surfaced.

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 short, front-loaded, and contains no filler; both sentences earn their place. It loses one point because the second sentence relies on the undefined 'title' concept rather than connecting to a schema parameter.

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?

For an agent to invoke this tool, the most critical fact - how to pass the Wikipedia title - is absent, and no output schema compensates. The mismatch between description and input schema leaves the tool unusable as documented.

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 implies a title input, but the schema exposes ref, url, city, feed, host, json, and path - none labeled as a Wikipedia title. The description adds no mapping or instruction for supplying the title, and the existing parameter descriptions are unrelated to the tool's purpose. This makes correct invocation impossible without guessing.

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 and object: 'Check whether a Wikipedia title exists.' This is clear and not tautological. It earns a 4 rather than 5 because it does not differentiate wiki-title-ok from sibling validators such as browser-url-ok or domain-shape, and it gives no hint of which input parameter carries the title.

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 about when to prefer this tool over sibling tools, nor any exclusion criteria. The intended use is only implied by the purpose statement, so an agent has no help choosing between wiki-title-ok and other *-ok/*-shape validators.

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