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

No annotations are provided, so the description carries the full burden of behavioral disclosure. The only behavioral note is 'Title discarded after the call,' which is a trivial data-retention fact. It does not disclose side effects, error behavior, return format, or the fact that the tool seems to validate many different input types, not just Wikipedia titles. The mismatch between the described purpose and the schema parameters is a significant undisclosed trait.

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 short (two sentences), which is concise but under-specified. It front-loads the core action, but it lacks essential information about input mapping and scope. Conciseness is not merely brevity; it must be appropriately sized to convey necessary details. Here, the brevity leaves the agent with no actionable guidance.

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 a tool with nine parameters, no output schema, and no annotations, the description is grossly incomplete. It does not explain how to construct a valid call, which parameter is the title, what the response looks like, or any error conditions. The tool appears to be a generic shape-checker based on the parameter descriptions, yet the description claims a very narrow purpose. The gap between claimed and actual behavior makes this tool effectively unusable without additional external knowledge.

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%, but the description adds no meaning beyond the schema. The parameter descriptions themselves are inconsistent with the tool's stated purpose (e.g., 'Git ref name; discarded after the shape check' has no connection to Wikipedia titles). The tool description never clarifies which parameter is the title, making it impossible to know how to pass the required input. The description actually detracts from clarity rather than adding value.

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 action: 'Check whether a Wikipedia title exists.' However, the input schema contains nine unrelated parameters (ref, url, city, feed, host, json, path, zone, query) with no obvious parameter for a Wikipedia title. The description does not specify which parameter carries the title, so the stated purpose cannot be mapped to the actual interface. It also does not distinguish itself from siblings like search-query-len or validate-json, which also deal with text validation.

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?

No guidance is given on when to use this tool versus alternatives. There is no mention of prerequisites, exclusions, or typical use cases. The sibling tools cover similar validation tasks, but the description offers no routing hints, leaving the agent to guess based solely on the name.

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