list_captures

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

With no annotations, the description carries the burden of behavioral disclosure. It usefully signals that the buffer is ephemeral and that the result reflects whatever is currently retained, implying a read-only listing. However, it does not mention ordering, empty-buffer behavior, or whether the listing affects buffer state.

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 no filler. Every word adds meaning: 'all captures', 'currently retained', and 'ephemeral ring buffer' all contribute to accurate selection and invocation.

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 list operation with an output schema available, the description is complete enough. It tells the agent exactly what the tool returns and the scope of that return, and nothing else is needed 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 has zero parameters, and the schema confirms this, so there is no parameter documentation burden. The description focuses on the operation rather than inputs, which is appropriate for a no-argument tool.

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 ('Lists') and a clear resource ('all captures') with an explicit scope ('currently retained in the ephemeral ring buffer'). This distinguishes it from sibling tools like search_capture and get_capture_slice, which imply filtering or partial access.

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 gives clear context: use this tool when you need the complete set of currently retained captures. It does not explicitly name alternatives or exclusion conditions, so it stops short of a 5, but the intent is not left to inference.

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