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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, so the safety profile is established. The description adds the 'Subscription-gated' constraint, which is a meaningful behavioral condition not captured by the annotations. This provides useful context about access requirements beyond what the schema or annotations communicate.

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 sentence that front-loads the most important attribute ('Subscription-gated') and packs in the key contents (field, metric, filter, sort, evidence) without waste. Every word contributes to understanding the tool's scope and constraint, making it highly concise and well-structured.

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 narrow scope (retrieving a catalog for one model) and the presence of an output schema that likely details the return structure, the description is sufficient. It lists the types of components covered and the subscription gate. It does not describe pagination or detailed usage, but these are not necessary for a catalog tool with a rich output schema and full parameter documentation.

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?

Schema coverage is 100% because the only parameter, model_key, is described as 'Required governed semantic model key.' The description's phrase 'for one governed semantic model' reinforces that the parameter identifies a model, but it does not add syntax, format, or additional meaning beyond the schema. With full schema coverage, a baseline 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 clearly identifies the tool as a 'field, metric, filter, sort, and evidence contract' for a specific semantic model, which conveys its role as a catalog for query components. It does not use a verb+resource construction, but the scope is specific enough to distinguish it from sibling tools like atlas7_model_catalog. The phrase 'for one governed semantic model' signals that it is per-model, adding clarity.

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 implies that this tool is used to retrieve the catalog of fields, metrics, filters, sorts, and evidence for a given model, but it does not explicitly state when to prefer it over alternatives like atlas7_semantic_query or atlas7_compile_query. No exclusions or direct comparisons are provided, so the usage context is inferred rather than explicit.

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