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

The description does disclose one behavioral trait: 'Title discarded after the call,' which tells the agent the input is not persisted. With no annotations provided, however, it leaves other important behaviors unclear, such as whether a live Wikipedia lookup occurs, what the result looks like, and whether all the other schema parameters are ignored.

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 tightly written with the main purpose front-loaded and no filler. The second sentence adds a behavioral note that earns its place. It is concise, though slightly under-specified for an input schema with eight heterogeneous 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?

For an eight-parameter schema with no output schema, a two-sentence description is not enough to let an agent call the tool correctly. It never states which parameter is the Wikipedia title, what a positive or negative result means, or whether the other schema fields are relevant. The definition leaves too much for the agent to guess.

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?

Every input schema property has its own description, so schema coverage is high and the description would only need to add marginal value. But the description references a 'title' parameter that does not exist in the schema, while the actual parameters (ref, url, city, feed, host, json, path) are described in terms of other purposes. This creates real ambiguity about which property should be populated.

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 concrete operation: 'Check whether a Wikipedia title exists,' which names both the action and the resource. It is clear on a high level and the tool name reinforces the Wikipedia-title focus. However, it doesn't differentiate this from sibling validation tools, and the schema contains no 'title' property, creating a purpose-to-schema mismatch.

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 use this tool instead of sibling alternatives like validate-json, normalize-url, or web-fetch. The description offers no 'use when' conditions, no exclusions, and no pointer to a better alternative. Usage context is only weakly implied by the tool name.

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