update_income_attachment

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

Annotations already mark destructiveHint true, but the description adds value by specifying Base64 encoding for data and the user confirmation step. No contradictions, and it enriches understanding of the tool's behavior beyond the annotation alone.

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 extremely concise, using one line with a warning emoji. It avoids redundancy and communicates key points efficiently, though it could be slightly expanded for completeness.

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?

With 3 required parameters and an output schema, the description omits any mention of return values or side effects. It does not clarify whether the attachment is replaced or added, leaving gaps for the agent, especially given the destructive hint.

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 0%, so description must compensate. It clarifies that 'data' is in Base64, but income_id and filename receive no additional explanation beyond their names. Only one of three parameters benefits from the description.

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 'Updates the attachment of an income' with specific verb and resource. It also mentions Base64 data format. However, it does not differentiate from sibling tools like delete_income_attachment or get_income_attachment, missing explicit scope distinction.

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 includes 'Confirm with user' as a usage note, advising confirmation before action. However, it provides no guidance on when to use this tool versus other attachment-related tools (e.g., delete_income_attachment) or context for selection.

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