memory_list_contexts

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It makes the read-only enumeration behavior clear by using 'List' and describes the returned information. It does not mention edge cases such as whether empty namespaces are included or whether results are ordered, but for a zero-parameter listing tool these are minor omissions.

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, compact sentence that front-loads the action and the result. Every word contributes meaning, and there is no filler or repetition.

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?

This is a very simple tool with no parameters and no output schema. The description states both what is listed and what metric is returned (memory counts per namespace), which is sufficient for an agent to invoke it 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 accepts zero parameters and the input schema has no properties, so there is nothing for the description to add about parameters. The baseline of 4 for a no-parameter tool applies.

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' with a clear resource ('context namespaces') and states the exact output ('the number of memories in each'). It is unambiguous and unlikely to be confused with the sibling tools, though it does not explicitly call out how it differs from any sibling.

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 intended usage is implied: an agent should use this tool when it needs an overview of context namespaces and their memory counts. However, there is no explicit guidance about when not to use it or which alternative sibling tool to choose instead.

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