xero_attach_file_to_expense

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action is to attach a file, implying a write/mutation operation, but doesn't mention required permissions, rate limits, file size constraints, supported file types beyond 'PDF, image', or what happens on success/failure. For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

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, efficient sentence that front-loads the core action and resource. It uses parentheses for concise clarifications ('PDF, image' and 'bank transaction') without unnecessary elaboration. Every word contributes directly to understanding the tool's function, making it well-structured and appropriately sized.

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 the tool's complexity as a mutation operation with no annotations and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., permissions, errors), output expectations, and differentiation from sibling tools. While concise, it doesn't compensate for the missing structured data, leaving gaps for effective agent use.

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 100%, with both parameters ('bankTransactionId' and 'filePath') documented in the schema. The description adds minimal value beyond the schema by implying the file types ('PDF, image') and that the expense is a 'bank transaction', but doesn't provide additional syntax, format details, or constraints. This meets the baseline score of 3 for high schema coverage.

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 action ('Attach a file') and the target resource ('to an existing Xero expense (bank transaction)'), specifying the verb and resource. However, it doesn't explicitly differentiate from sibling tools like 'xero_attach_file_to_invoice' or 'xero_attach_file_to_receipt', which attach files to different Xero entities, leaving some ambiguity about when to choose this specific tool over similar ones.

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 no guidance on when to use this tool versus alternatives. It mentions attaching to an 'existing Xero expense' but doesn't specify prerequisites, exclusions, or compare it to sibling tools like 'xero_attach_file' (which might have broader scope) or other attachment tools for invoices or receipts. This lack of contextual direction leaves the agent without clear usage criteria.

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