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

Annotations already declare the operation as read-only, idempotent, and non-destructive. The description adds valuable behavioral context not present in annotations: the cost ('Free') and the specific structure of returned data ('dimensions, weights, artifacts summary, and rubric status'), which compensates for the missing output schema.

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 consists of two highly efficient sentences. The first front-loads the action and resource with specific detail fields; the second provides sourcing and cost constraints. No words are wasted, and every clause delivers actionable information.

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 simple read-only retrieval tool with one parameter and strong annotations, the description is complete. It compensates for the missing output schema by detailing the return structure in the text, and the 100% schema coverage means no additional parameter documentation is needed.

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?

With 100% schema description coverage, the baseline is 3. The description repeats the parameter sourcing information already present in the schema ('model_id from atlas_create_custom_eval_model or atlas_list_custom_eval_models') but does not add additional semantic meaning, constraints, or format details beyond what the schema provides.

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 uses a specific verb ('Get') with a clear resource ('custom evaluation model') and enumerates the specific data returned ('dimensions, weights, artifacts summary, and rubric status'). This distinguishes it from sibling tools like atlas_list_custom_eval_models (which likely returns summaries) and atlas_create_custom_eval_model.

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 explicit guidance on sourcing the required parameter ('model_id from atlas_create_custom_eval_model or atlas_list_custom_eval_models') and includes cost information ('Free'). While it doesn't explicitly state 'when not to use' alternatives, the parameter sourcing instructions effectively indicate prerequisite workflows.

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