list_entities

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

With no annotations, the description carries the full burden of behavioral disclosure. It does convey that the operation is a read-only listing (via 'List') and that results are scoped to the reader's visibility, which is useful. However, it does not disclose potential limitations (e.g., pagination, ordering, whether identities are returned as IDs or full objects, or error behavior). The description is minimally transparent but not misleading.

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, tightly worded sentence with no filler words or redundant information. It front-loads the action and resource immediately. Every word contributes to understanding the tool's purpose and scope, making it a model of conciseness.

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 tool with no parameters and an existing output schema, the description is largely sufficient. It specifies what the tool does and the permission context ('visible to the current reader'). The only notable gap is the absence of usage guidance relative to sibling tools, but this is more of a usage-guidelines concern. Given the simplicity of the tool, the description is adequately complete without needing to detail return structures or side effects.

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 the schema coverage is 100% because the properties object is empty. Per calibration, a baseline of 4 applies when params are absent. The description does not need to explain parameters, and it doesn't introduce any ambiguity about parameter usage. It adds no parameter semantics because there are none to add, leaving the baseline score appropriate.

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 clearly states the specific action (List), the resource (entity identities), and the scope (visible to the current reader). This distinguishes it from siblings like describe_entity, which would provide detailed information about a single entity, and search_brain, which implies a search operation. The verb and object are unambiguous and not tautological.

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 provides no explicit guidance on when to use this tool versus alternatives. While the purpose implies it should be used for enumerating accessible entities, there is no mention of exclusions or scenarios where a sibling tool would be more appropriate. The agent is left to infer usage solely from the tool's name and one-line description.

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