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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds value by specifying what the checks detect (stale pages, orphaned knowledge), but no deeper behavioral traits like output format or whether fixes are applied. This is adequate but not exceptional.

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?

One concise sentence that front-loads the main action ('Run maintenance checks') and then elaborates with specific examples. No filler, no repetition of schema or annotations.

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, non-destructive tool with rich annotations, the description provides enough context about its purpose and typical findings. The absence of an output schema is not a major gap because the described behavior (finding issues) implies a list or report, which is sufficient for invoking the tool correctly.

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 and schema coverage is 100%, so there is nothing for the description to add. Baseline 4 applies for zero-parameter tools; the description is not required to explain any arguments.

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 ('run') and a clear resource ('your brain'), then specifies concrete outcomes: 'find stale pages, orphaned knowledge, and other issues.' This clearly distinguishes it from sibling tools like brain_query or brain_add, which operate differently.

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 when to use the tool—whenever maintenance or health checks on the brain knowledge base are needed—and names the kind of issues found. However, it does not explicitly mention when not to use it or compare it to alternatives such as brain_status or brain_query, leaving some routing to inference.

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