Get Attachment

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

Annotations already indicate `readOnlyHint: true`, confirming it's a safe read operation. The description adds that the response includes filename, byte count, and base64 content for local decoding, providing concrete behavioral context beyond the annotation.

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?

Two sentences with no filler. Information is front-loaded: action, output format, required inputs, and process hint. Every word earns its place.

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 download tool with no output schema, the description fully explains the return format (filename, byte count, base64 content) and the necessary parameters. No critical information is missing given the tool's simplicity and the presence of 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?

Input schema describes both parameters with 100% coverage. The description adds meaning by explaining that `attachmentId` can be either an id or an unambiguous filename selector, and that `itemId` is the 'parent Bitwarden item id'. This supplements the schema's definitions.

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?

Description clearly states 'download an attachment from a parent item' and specifies the output format (raw bytes as contentBase64). It distinguishes from sibling tools like `keychain_delete_attachment` and `keychain_create_attachment` by focusing exclusively on retrieval.

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?

Provides explicit guidance: pass itemId and attachmentId or an unambiguous filename selector resolved from item metadata. It implies when to use (downloading an attachment) but does not explicitly state when not to use or list alternatives. The instruction to resolve filename from metadata before calling is a useful guideline.

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