download_attachment

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

With no annotations, the description carries the full behavioral burden and does add real value: it discloses that the return is a path on the bridge host and warns that view-once media lands in a temporary folder and is deleted soon ('never keep it'). It omits failure modes, permissions, and whether the download is cached, but the ephemeral-media warning is genuinely useful context.

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?

Front-loads the core action and return value, follows with the critical view-once warning, and closes with the Args block. Every element earns its place given the 0% schema coverage, though the format is slightly blocky rather than prose-tight.

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?

An output schema exists, so return values need not be explained, yet the description still notes the returned path. Both parameters are documented and the ephemeral-media caveat covers the main behavioral risk for this tool, leaving only minor gaps like error handling.

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%, so the description must compensate, and it does: message_id is explained as coming from the channel event and 'to' as a chat alias that may be omitted for the sole subscribed target. It adds meaning beyond a bare 'To'/'Message Id' title, though it does not specify format or ID shape in detail.

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?

States a specific verb (download) and a precise resource (a message's photo, video or voice clip) and notes it returns a path on the bridge host, which clearly separates it from send_file/share_media/transcribe_share. It stops short of naming any sibling alternative, so it is clear but does not explicitly differentiate.

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?

It gives practical context: message_id comes from the channel event, and 'to' should be omitted for the sole subscribed target. However, there is no explicit when-to-use-vs-alternatives guidance (e.g. when to download_attachment versus transcribe_share or share_media), so usage is only implied.

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