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

With no annotations, the description carries the full transparency burden. It discloses that the tool returns CLI/SDK steps, that encryption is zero-knowledge, and that execution must be on the agent's machine. It does not explicitly state that the tool is non-destructive and only provides instructions, but this is implied. A more explicit statement would improve score.

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 two sentences, front-loaded with the core purpose. The second sentence adds critical constraints (zero-knowledge, local execution). Every word contributes meaning, and there is no redundancy or fluff.

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 (no parameters, no output schema), the description is complete. It explains what the tool does, what it returns, and a key constraint. The user can understand exactly when and how to use this tool. No additional information is necessary.

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 adds meaning beyond the empty schema by explaining that the output is CLI/SDK steps. No parameter details are needed, and the description compensates for the lack of parameters by describing the tool's purpose.

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 returns CLI/SDK steps to create or restore an encrypted backup. It uses specific verbs (CREATE/RESTORE) and resource (encrypted backup), and the name 'vault_how_to_backup' makes it distinct from sibling vault tools that perform actions like delete or list.

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 implies usage: when you need the steps to create or restore a backup. However, it does not explicitly state when not to use it (e.g., if you want to actually perform the backup or use other vault tools). The context of sibling tools provides differentiation, but the description could be more explicit about alternatives.

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