billy_attach_file_to_invoice

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

With no annotations provided, the description carries the full burden. It clearly states 'WRITE — requires confirm:true' and the schema explains the dry-run behavior for confirm. However, it does not disclose if the file is copied or linked, or any other side effects.

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 very short (one sentence plus note) and front-loaded. It is efficient but could include brief parameter explanations without significant bloat.

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?

Given no output schema and 3 parameters, the description misses key context: how to get fileId, prerequisite steps, and what happens after attachment. The sibling tools (billy_list_files, billy_upload_file) hint at the workflow but are not referenced.

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 description coverage is low (33%: only confirm described). The tool description does not add any additional meaning for fileId or invoiceId beyond their names. It should explain where to obtain fileId (e.g., from billy_list_files) and the format of invoiceId.

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 'Attach an uploaded file to an invoice' using a specific verb (attach) and resources (file, invoice). This distinguishes it from siblings like billy_attach_file_to_bill and billy_upload_file.

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 (attaching an uploaded file to an invoice) but provides no explicit when-to-use, when-not, or alternatives. It lacks guidance on prerequisites like requiring a prior upload via billy_upload_file.

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