Create Attachment

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

Annotations indicate readOnlyHint=false and destructiveHint=false, so the tool is a non-destructive mutation. The description adds valuable context: it returns the updated item summary with redaction rules (secrets hidden unless reveal is allowed), and explicitly ties to the reveal parameter. This goes beyond annotations.

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, well-structured sentence that front-loads the action and resource. Every clause adds value: attaching bytes, return format, redaction rule. No filler or redundancy.

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 tool with no output schema, the description covers core behavior (attach, return summary with redaction) and mentions the reveal parameter. However, it omits edge cases like non-existent items or size limits, which are minor given the schema and annotations.

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 100%, so baseline is 3. The description adds meaning by explaining that contentBase64 is not a filesystem path and that reveal controls secret redaction. It links the return behavior to the reveal parameter, enriching understanding beyond schema descriptions.

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 identifies the tool's action: attaching base64-encoded file bytes to an existing item. It specifies the resource (existing Bitwarden item) and distinguishes from sibling tools like keychain_get_attachment or keychain_delete_attachment by focusing on creation.

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 for attaching files to items but does not provide explicit guidance on when to use this tool versus alternatives like keychain_get_attachment or keychain_delete_attachment. No when-not or alternative tools are mentioned.

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