khwan_cores

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

With no annotations, the description carries the full burden. It goes beyond a simple list by defining what a core is ('fully isolated brain') and explaining the selection mechanism, which helps an agent understand the statefulness and isolation properties of the tool. Since it is a list operation, the read-only nature is reasonably understood.

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?

Two short, focused paragraphs with no filler. The core purpose is front-loaded, and the explanation about isolating and selecting is directly useful without redundancy.

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?

Given the tool has zero parameters and an output schema, the description fully covers what an agent needs: what the tool lists, what cores are, and how to proceed after listing. Nothing essential is missing.

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 no parameter explanation is necessary. The description does add value by pointing to an environment variable rather than a parameter, which is a contextual extra.

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 ('isolated cores (brains) available on this account'), making the tool's function immediately clear. It also distinguishes this from the sibling memory operation tools by focusing on core discovery rather than manipulation.

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?

It explains how to use the selected core — via the KHWAN_CORE environment variable — which gives practical usage context. It does not explicitly name sibling alternatives or state when not to use this tool, but the listing-plus-selection flow is clear enough.

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