memory_stats

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

Annotations already mark the tool as readOnlyHint and idempotentHint, so the description does not need to restate safety. It adds meaningful behavioral context by naming the categories of statistics returned, which helps the agent know what to expect beyond the annotation hints. No contradiction with annotations exists.

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 extremely compact and front-loaded: the verb and resource appear immediately, followed by a concise list of return contents. The bilingual version adds little overhead and every phrase contributes useful 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 zero-parameter, read-only statistics tool, the description provides a solid overview of what will be returned. However, there is no output schema, and terms like 'write log status' and 'semantic coverage' are not expanded, so an agent may not know the exact format or meaning until after calling it.

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 zero parameters, so the description carries no parameter documentation burden. The baseline of 4 applies because there are no parameters whose semantics need elaboration.

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 ('Return') and a clear resource ('index statistics'), then enumerates the exact data points returned: chunk count, per-domain distribution, write log status, semantic coverage, and db size. This clearly distinguishes it from sibling tools like memory_search or memory_list, which have different purposes.

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 state when to use this tool versus alternatives, such as memory_domains for domain-specific information or memory_history for write log details. The usage context is only implied by the tool name and the nature of statistics; there is no explicit guidance or exclusions.

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