List vaults

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

With no annotations provided, the description carries the full behavioral transparency burden. It explains what the tool reports: file existence, keychain storage of master password, and session unlock state. This goes beyond a generic 'list vaults' and informs the agent about latent checks without requiring external knowledge.

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 sentence that packs multiple relevant details without unnecessary words. It is front-loaded with the primary action and scope, and each clause adds value to the agent's understanding.

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 0-parameter tool with no output schema, the description sufficiently explains what the returned data covers (vault registration, file existence, keychain status, unlock state). It does not specify the exact return format, but the key attributes are enumerated, which is adequate for an agent to know what to expect.

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 correctly focuses on behavior rather than parameters, and no parameter documentation is needed.

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 uses a specific verb ('Lists') and clearly identifies the resource ('Enpass vaults registered on this machine'). It distinguishes the tool from siblings like list_items by scoping to vault-level metadata rather than items or attachments.

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 when to use the tool (when needing vault registration/status info) but does not explicitly state alternatives or exclusions relative to sibling tools. It lacks phrases like 'use this instead of' or 'when you need' that would provide stronger guidance.

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