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

No annotations are present, so the description carries the burden. It discloses that the operation is local, cache-based, and restricted to the operator host, which implies a read-only listing. However, it does not explain failure modes, permissions, or what 'utility metrics' consist of.

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, front-loaded sentence with a clear scope tag and a separate host restriction. Every phrase earns its place; no filler or redundant explanation.

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, no-output-schema tool, the description covers the core purpose and host restriction. The vague phrase 'utility metrics' is a notable gap, as the agent cannot know exactly what metrics are returned or in what form.

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 baseline is 4. The input schema already shows an empty properties object, and the description adds no parameter information because none is needed.

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 ('List') and resource ('cached gbrain note names') with an added scope ('utility metrics', 'Operator host only'). It clearly differs from siblings like gbrain_get and gbrain_search by indicating a listing/enumeration operation.

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 '[Local ops]' prefix and 'Operator host only' restriction provide clear usage context and an exclusion (do not run outside the operator host). It does not explicitly name alternatives such as gbrain_get or gbrain_search, but the local/cached scoping makes the intended environment clear.

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