add_service_ssh_key_to_library

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

With no annotations, the description carries the full burden. It states 'Plain write — no billing impact, not destructive,' which directly informs the agent about safety and cost. It also mentions the required auth scope. This is valuable transparency beyond the schema.

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 paragraph with four well-organized sentences: purpose, distinction, permissions/safety, and parameter hint. Every sentence adds value without redundancy. It is concise and front-loaded with the primary action.

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?

Given the tool's simplicity (3 parameters, no output schema), the description covers purpose, sibling differentiation, permissions, safety, and parameter source. It does not detail error handling or idempotency, but for a write tool with no output schema, this is reasonably complete.

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 input schema already provides descriptions for all three parameters (100% coverage). The description adds only a minor hint about service_id source. Baseline 3 is appropriate since the schema does the heavy lifting and the description adds marginal value.

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 the tool registers an SSH key into a legacy VPS's key library, which is distinct from direct installation via add_service_ssh_key. It names the specific platform (Virtualizor) and references the library listing tool, making the purpose unambiguous and differentiating it from siblings.

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 contrasts with add_service_ssh_key and mentions the required scope 'services:write'. While it doesn't list all scenarios for when not to use it, the distinction and scope information provide clear guidance. It also indicates the source of the service_id parameter.

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