set_mode

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

Beyond the annotations, the description reveals the self-elevation prevention mechanism and the environment-variable escape hatch. This is important behavioral context that an agent could not infer from readOnlyHint, destructiveHint, or idempotentHint alone.

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 well-structured and appropriately sized: a one-sentence purpose, a focused security explanation, and a compact Args/Returns block. Every sentence adds meaningful guidance, with the most important usage constraint front-loaded.

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 simple mode-change tool, the description covers the action, the constraints, the security rationale, the parameter list, and the return value. No critical operational detail appears to be 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 Args section merely lists 'mode, persist' with no additional explanation of their meanings, values, or effects. Although the input schema contains some descriptions, the provided context reports 0% schema description coverage, so the description needed to compensate and did not.

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 it changes the server's permission mode (SAFE / NORMAL / ADMIN), naming a specific verb, resource, and the possible values. It is distinct from all listed sibling tools, which are system, file, package, or terminal operations rather than mode switching.

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 explicitly explains when the mode can be lowered versus raised: lowering is always allowed, while raising requires ADMIN mode or the UBUNTU_CONTROL_MODE environment variable. It also explains the security rationale, giving an agent the exact constraints for using the tool safely.

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