get_index_usage

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

Without annotations, the description carries the burden. It states the tool reads from sys.dm_db_index_usage_stats, indicating a read operation, but does not mention permissions, potential performance impact, or whether results are volatile.

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, efficient sentence that immediately states the purpose and key details. It is front-loaded with the action and resource, with no unnecessary words.

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 tool with 4 parameters and no output schema, the description adequately covers return values (seeks, scans, lookups, updates) and source. It lacks details on result format or pagination, but is sufficient for typical use.

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 input schema has 100% coverage of parameter descriptions, but the description adds value by linking the tool to the specific system view (sys.dm_db_index_usage_stats), providing semantic context beyond the schema fields.

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 specifies the verb 'get' and the resource 'index usage statistics' with specific metrics (seeks, scans, lookups, updates) and the source system view. It distinguishes this tool from siblings like get_indexes which returns metadata.

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 usage for retrieving index usage stats but does not provide explicit guidance on when to prefer this over alternatives like get_indexes or get_missing_indexes, nor when not to use it.

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