memory_stats

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safe-read profile is covered. The description adds useful context about what the stats include (scope/kind/status counts, storage location, vector-search status), but since an output schema exists this is largely a peek at return values rather than deep behavioral disclosure.

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?

A single terse sentence with semicolon-separated facets and no filler; the most important element (counts per scope/kind/status) is front-loaded. It is a noun-phrase fragment rather than a full clause, but nothing is wasted.

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 stats tool with an output schema present, the description need not detail return format. It covers what the tool reports and its safety profile implicitly via annotations, leaving only usage routing unaddressed.

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 takes zero parameters, so per the rubric the baseline is 4. There is nothing for the description to clarify about inputs, and schema coverage is trivially 100%.

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?

States a specific resource (memory statistics) and enumerates the dimensions counted: per scope, kind, and status, plus storage location and vector-search state. It is clearly distinct from siblings like memory_recall, memory_list, or memory_remember, though it does not explicitly name any alternative.

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?

No when-to-use guidance is given beyond the implicit fact that this is a stats/inspection tool. There is no mention of prerequisites, when to prefer it over memory_list or memory_brief, or any exclusions.

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