list_available_shells

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

No annotations exist, so the description carries the full behavioral burden, yet it discloses nothing about permissions, whether the call is a cheap read, whether results are cached, or what happens if the guest agent is unreachable. The only implicit signal is that it is a non-destructive lookup.

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?

Five words with zero redundancy, but it is a bare noun phrase rather than a structured definition, and the terseness reflects under-specification rather than discipline.

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 two-parameter read tool with no output schema, the description is minimally sufficient to identify the operation. It is still missing the refresh semantics and the guest-agent prerequisite an agent needs before calling 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?

Schema coverage is 50%: 'vm' is documented as 'VM name or UUID', but 'refresh' has no description in the schema and none in the description. The description adds no meaning about what refresh invalidates or when the caller should set it, leaving half the parameters opaque.

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 fragment 'Shells available in the guest' conveys that the tool enumerates shells inside a guest VM, which is slightly more than the name alone. However, it reads close to a restatement of the tool name and never names the sibling it complements (e.g. execute_command) or what a 'shell' means here (bash, sh, powershell).

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?

There is no when-to-use guidance at all: no statement of prerequisites (guest OS detected, guest agent running), no mention of using the result with execute_command, and no exclusions. The agent must infer the workflow from the sibling list.

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