base64

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

No annotations are provided, so the description must carry the full burden of behavioral disclosure. It only states 'Encode or decode base64,' which is a minimal restatement of the tool's name and does not disclose default behavior (e.g., default action is encode per schema), output format, or any limitations. This is insufficient transparency for a tool without annotations.

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—one sentence with no wasted words. It is front-loaded, but the extreme brevity leaves out important context that other dimensions need, so it is not a perfect score.

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 has no annotations and no output schema, the description needs to provide more context about return values and usage. It is too minimal to be considered complete; the agent would need to infer expected output and behavior from the schema alone.

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 description adds no information about the parameters text and action. However, the input schema already provides full descriptions for both parameters (100% coverage), so per the scoring baseline, a score of 3 is appropriate.

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 'Encode or decode base64' clearly states the tool's function with a specific verb and resource, making its purpose unambiguous. However, it does not explicitly distinguish this tool from sibling encoding tools like url_encode or hex_encode, so it falls short of a 5.

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 tool versus alternatives. It does not mention when base64 is preferred over other encoding methods or any exclusions, leaving the agent to infer usage.

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