list_agents

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

With no annotations, the description fully carries the transparency burden. It discloses the tool's read-only nature, the specific information returned (directory confinement, write/shell enablement, step and timeout budgets), and its behavior when NVIDIA_API_KEY is missing. This is rich behavioral detail.

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 compact yet comprehensive, with each sentence earning its place. The first sentence states purpose, the second gives usage context and behaviors, and the third adds the API-key check nuance. It is front-loaded and free of 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?

Despite the tool's simplicity, the description covers purpose, usage timing, output expectations, and edge-case behavior (missing API key). Since an output schema exists, the description need not detail return values, and it sufficiently covers the operational context.

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 description appropriately avoids inventing parameter semantics and instead clarifies what the tool outputs, which is consistent with a no-argument introspection 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 opens with 'Show what SubMCP can do right now: profiles, model, sandbox root, and capability gates,' which clearly identifies the tool's purpose as an informational listing. It distinguishes from sibling delegate tools by focusing on capability introspection rather than execution.

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?

Explicit guidance is provided: 'Call this before your first delegate in a session, or when a delegation behaves unexpectedly.' This gives clear when-to-use context, and the note about needing no API key frames it as a setup check, effectively differentiating from delegation alternatives.

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