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

No annotations are provided, so the description carries full responsibility for disclosing behavior. It does not state whether the tool is read-only, whether it has side effects, what it returns in detail, or any computational cost. The phrase 'ΔE+ΔC must be ~0' hints at a mathematical validation but doesn't explain the tool's execution or output format. This is a significant gap given zero annotation coverage.

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 brief (two sentences) and front-loads the key metrics. It avoids verbose filler, but the cryptic phrasing ('mirrored cost', 'Smart Frame') reduces clarity. It's concise in length but not optimally structured for comprehension; still, it earns a 4 for being tightly written.

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?

With no output schema, the description must explain what the tool returns and how to interpret it. It mentions 'residual summary' but doesn't specify the return format, units, or how the metrics relate. It also doesn't clarify how this differs from the sibling cddg_residual_summary, leaving the agent with incomplete context for a no-param tool.

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, and the schema is empty (100% coverage). The description doesn't need to explain parameters, and with none present, there is nothing to miss. Baseline of 4 is appropriate because the description doesn't add parameter info, but it isn't required. No parameter-related confusion exists.

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 names specific outputs (global residual energy, mirrored cost, dual error) and calls itself a 'Smart Frame residual summary,' implying a read/query action. However, it lacks an explicit verb like 'get' or 'compute,' and the phrasing is cryptic—an agent may not know what the tool actually does beyond its name. It is not a pure tautology but is vague enough to leave purpose partially inferred.

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 explicit guidance on when to use this tool versus alternatives. Sibling tools like cddg_residual_summary and cddg_step exist, but the description doesn't differentiate or state conditions for use. The only contextual hint is 'residual summary,' which implies a diagnostic use, but nothing is stated about when to choose this over cddg_residual_summary.

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