knowledge_stats

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

The annotations already declare the tool as read-only, non-destructive, idempotent, and not open-world. The description adds value by specifying the output's subject matter (index sizes and document budget), which is not evident from annotations alone. No contradictions.

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, clear sentence that immediately conveys the tool's purpose. Every word is necessary; there is no redundancy or filler. It is front-loaded with the verb and key nouns.

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 absence of parameters and the presence of comprehensive annotations, the description is fully complete. It states what the tool reports, and the output schema (which exists) handles return value details. No gaps remain.

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 zero parameters, and schema description coverage is 100% (trivially). The description does not need to add parameter details since there are none. Baseline for no parameters is 4, and the description adequately describes the tool's output.

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 'Report' and specifies the resources: 'local knowledge index sizes and document budget'. It clearly distinguishes itself from sibling tools like 'search_knowledge' (searching) and 'index_knowledge' (indexing) by focusing on reporting statistics.

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 does not provide explicit guidelines on when to use this tool versus alternatives. It implies usage for monitoring or budgeting but lacks exclusions or comparisons to similar reporting tools (e.g., 'accounting_health_summary'). The context is clear but not directive.

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