Download ClassApp attachment locally

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

The description adds substantial context beyond annotations: it discloses that a new random local file is created and never overwritten, which explains the idempotentHint=false and destructiveHint=false annotations, and that path, bytes and SHA-256 are returned. It stops short of stating auth or permission requirements or any rate limits for the download.

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?

Four short sentences, each carrying distinct information: action and destination first, then filesystem behavior, then return values, then exclusions. No filler and no repetition of the title.

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 spelled out, and the description still gives a useful summary of them. The write behavior and non-overwrite guarantee cover the mutation risk, leaving only the undocumented parameter identities as a gap.

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 carry the burden, and it largely does not. 'Attached to a message' hints at the messageId scoping and 'no arbitrary URL or filename is accepted' indicates the IDs are opaque internal identifiers, but entityId, messageId and attachmentId are never individually explained or related to one another.

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: download an attachment belonging to a message into a configured private directory. It is clearly distinguishable from siblings such as classapp_read_message or classapp_search_notices, which do not write files to disk.

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 implied rather than stated: the agent can infer this is the tool for retrieving attachment content, and the negative scope ('Does not send messages or request read-status updates') rules out adjacent actions. However, no sibling tool is named as an alternative and no prerequisite is given (for example, whether messageId must first be obtained from classapp_read_message).

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