List attachments

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

With no annotations, the description carries the full behavioral burden. It adds useful context: the vault must be unlocked, and the output includes name, size, and MIME. However, it does not mention whether this is a read-only operation, what happens if the vault is locked, or any error behavior. It is adequate but not deeply transparent.

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 concise: two sentences, each with a clear purpose. The first sentence states the action and output, the second gives an alternative. No unnecessary words or repetition.

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 tool with no output schema, the description covers the core aspects: what it does, what it returns, a prerequisite (unlocked vault), and an alternative tool for a different use case. It lacks edge-case details (e.g., behavior when the vault is locked), but for a listing tool this is sufficient.

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 has 100% description coverage for both parameters ('vault' and 'uuid'). The description adds the qualifier that the vault must be unlocked, which provides slight additional meaning, but it does not significantly enhance the parameter semantics beyond what the schema already conveys. Baseline 3 is appropriate.

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's function: 'Lists the file attachments of an entry in an unlocked vault (name, size, MIME).' It uses a specific verb ('lists') and resource ('file attachments of an entry'), and explicitly distinguishes it from the sibling tool 'export_attachment' by noting that the latter is for getting the file itself.

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 provides explicit usage guidance: it says to use 'export_attachment' to get the file itself, implying this tool is for listing metadata (name, size, MIME). It also specifies the prerequisite that the vault must be unlocked, which tells the agent when the tool can be used.

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