Get Message Attachment Download

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: the call 'authorizes' (implying permission scoping) and returns a 'short-lived' URL, warning the agent the result expires and must be used promptly. It stops short of describing failure modes for missing attachments.

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?

One sentence, front-loaded with the action and ending on the returned artifact. No filler.

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 four required, entirely undescribed parameters and no output schema, the description should at minimum explain how the identifiers nest and what the URL response contains. It gives only the URL and its expiring nature, which is insufficient for a tool that must be invoked with a precise four-part addressing tuple.

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 0% for four required parameters, and the description supplies no compensating detail. It never mentions that platform, thread_id, and message_id form a hierarchy required to locate the attachment, nor what attachment_id refers to, leaving the schema as the only (undocumented) source.

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 pair and resource: authorizing an inbox attachment and returning a download URL. That is clear and distinguishable from read-only listing tools like get_inbox_thread_messages, though it never names the analogous sibling get_campaign_file_download to draw the boundary explicitly.

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?

Usage is only implied: the agent can infer this is the step to take when it needs to actually fetch attachment bytes. There is no explicit guidance on when this is needed versus when listing messages suffices, nor any mention of prerequisites.

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