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

Annotations (readOnlyHint, openWorldHint, destructiveHint) do not reveal that this is a placeholder. The description adds critical transparency by stating 'no live web search or fetch exists behind it yet', which is essential behavioral information beyond what annotations provide. This clearly tells the agent the tool performs no operation.

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 and front-loads the most critical fact ('NOT YET IMPLEMENTED') in the first sentence. Every sentence provides necessary information about the placeholder nature and no content is wasted.

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 placeholder tool with no output schema and a single generic parameter, the description is largely complete: it clearly states the tool is not functional. However, it could improve by explicitly pointing agents to a working alternative (e.g., 'use search instead'), so it is not a perfect 5.

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% for the single parameter, so the baseline is 3. The description does not add any meaning to the 'input' parameter beyond the generic capability payload example already in the schema.

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 explicitly states 'NOT YET IMPLEMENTED' and 'Placeholder listing reserving this capability slot', clearly conveying that this tool is a placeholder rather than a functioning web search. It does not explicitly compare against siblings like 'search' or 'fetch', but its purpose is unambiguous and not a tautology.

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 placeholder tool versus alternatives such as 'search' or 'fetch'. It merely states it is not implemented, leaving agents without direction to avoid it or choose a working substitute.

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