knowledge_stats

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

Annotations declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint, which already cover safety. The description adds that it reports 'local' knowledge index, which is useful context, but does not elaborate on what exactly is included (e.g., budget specifics, whether it aggregates across instances). No contradiction.

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 concise sentence that states exactly what the tool does. No fluff, perfectly front-loaded.

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?

Complexity is low with 0 parameters and a clear purpose. The output schema exists, so return values are presumably documented there. The description covers the main function (sizes and budget) but could mention whether it's instance-specific or aggregated, though 'local' hints at instance-level. Overall complete enough.

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 0 parameters, so schema coverage is 100% trivially. The description adds no parameter details because none exist. Baseline for 0 params is 4, and the description is adequate.

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 states the tool reports local knowledge index sizes and document budget, which is specific and distinguishes it from siblings like index_knowledge and search_knowledge. It lacks a verb like 'get' but the purpose is clear.

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 checking knowledge index stats, but does not explicitly state when to use this tool versus alternatives (e.g., index_knowledge or search_knowledge). No exclusions or contextual triggers are provided.

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