Upload transaction attachment

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

The only annotation is readOnlyHint=false, which already signals a write operation. The description adds no behavioral context beyond that, such as permission requirements, whether an existing attachment is overwritten, size limits, or what the response contains. It is consistent with the annotation but does little to enrich the agent's understanding.

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 two tight sentences, front-loading the purpose before the input-format note. There is no filler or redundancy, and it is appropriately sized for a simple upload tool.

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 simplicity, full schema coverage, and the presence of an output schema, the description is nearly complete for correct invocation. It omits any when-to-use guidance relative to siblings, but the essential purpose and input choice are covered.

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%, and the description merely repeats the schema's own explanation of filePath and attachmentData. Since the schema already documents all six parameters fully, the baseline score of 3 is appropriate; the description adds no meaning beyond structured fields.

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 specific verb and resource: 'Upload an attachment to a feed item (transaction).' This clearly separates it from the sibling feed_item_attachment_download, but it does not explicitly name the sibling or clarify boundaries with other feed-item tools.

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 gives input-format guidance ('Provide either base64 encoded attachment data or a file path (recommended)'), but this is parameter usage rather than tool usage. It never says when to choose this tool over alternatives like feed_item_note_update or feed_item_attachment_download, nor does it state prerequisites or exclusions.

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