call

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

With no annotations, the description carries the full burden. It transparently discloses that the tool is a stub, returns IntentStub, and is not implemented. This goes beyond merely stating it's non-functional; it specifies the only possible behavioral outcome (returning a stub object), which is exactly what an agent needs to know.

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 two short sentences that convey everything essential: it's a stub, what it returns, and that it's not implemented. Every word earns its place, and the key 'Honest STUB' is front-loaded. There is no fluff or repetition.

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 stub tool with no parameters, no output schema, and no annotations, the description captures everything an agent needs to know: it should not be used for real tasks. The mention of the return type (IntentStub) provides a complete picture, and there is no missing information that would cause the agent to call it incorrectly.

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?

There are zero parameters, so the baseline is 4. The description adds nothing about parameters because there is nothing to add. The schema coverage is 100% (vacuously), and the description doesn't need to compensate for any missing parameter information.

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 this is an 'Honest STUB' that 'returns IntentStub' and is 'Not implemented.' This leaves no ambiguity about its purpose: it is a placeholder and not a functional tool. It clearly differentiates itself from real tools by signaling its non-functional nature, even if it doesn't name siblings.

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 states 'Not implemented,' which strongly implies the agent should not call this tool for real work. While it doesn't explicitly suggest alternatives like 'use create_account instead,' the disclosure is sufficient to prevent misuse. The lack of alternative recommendations is a minor gap, but the instruction is clear and direct.

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