upload_attachment

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

No annotations are provided, so the description carries the burden. It discloses a behavioral trait: 'Requires two steps internally: creates the attachment record, then uploads the file content.' This is useful but does not cover other behavioral aspects like idempotency, failure modes, or side effects (e.g., does it overwrite an existing attachment?). It adds some transparency but is not comprehensive.

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, no fluff. The main action is front-loaded, and the internal two-step detail is relevant and concise. Every word earns its place, making this an efficient, well-structured description.

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 file-upload tool with 4 required parameters and no output schema or annotations, the description provides the two-step process but omits key contextual details: what the tool returns (e.g., the created attachment ID), any file size or format limits, and whether it is a pure create operation. These gaps mean an agent cannot fully anticipate the tool's behavior, though the description covers the core action.

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 75% (3 of 4 parameters have descriptions), which is not high enough to trigger the baseline 3. The description does not compensate: it adds little meaning beyond the schema—it mentions 'file content' and 'Firefly III object' but does not clarify the 'filename' parameter (which lacks a schema description) or any format constraints. The description does not enrich parameter understanding.

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 states a clear verb+resource: 'Upload a file and attach it to a Firefly III object'. It also gives an example ('a transaction') and distinguishes itself from sibling attachment tools (list/get/delete) by focusing on the upload/attach action. However, it does not explicitly name alternatives or mention it is the create operation for attachments, so it stops short of a 5.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention when to prefer upload_attachment over other attachment tools (list_attachments, get_attachment, delete_attachment) or any prerequisites. The agent must infer usage solely from the tool name and sibling context.

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