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

With no annotations, the description must carry the full burden. It discloses that the tool is a guide and that following it leads to learning the correct workflow. This is sufficient for a static, non-mutating guide tool. There are no hidden side effects or complex behaviors to disclose.

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 a single, front-loaded sentence: 'Usage guide for xmp4 tools — read this first to learn the correct workflow'. Every word earns its place, no fluff, and the key action ('read this first') is immediately clear.

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?

Given the tool's low complexity (no params, no output schema), the description is complete enough for an agent to know when and how to use it. It clearly signals the tool's role as an onboarding guide within a suite of sibling tools. It could mention what the guide contains, but that is not necessary for basic selection.

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 tool has zero parameters, so per the rubric the baseline score is 4. The description naturally adds no parameter detail, but nothing is needed. The schema is empty and the description appropriately avoids inventing irrelevant 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 clearly identifies the tool as a usage guide for xmp4 tools with the directive to read it first. This distinguishes it from all sibling tools, which are specific functional utilities (e.g., xmp4_grep, xmp4_search). The purpose is unambiguous and actionable.

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 explicitly states 'read this first', which is a clear when-to-use instruction. It implies the tool should be consulted before using other xmp4 tools. However, it does not explicitly mention when not to use it or alternative tools, so it falls just short of a 5.

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