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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower, and the description adds real value on top: 'never message bodies' explicitly bounds the payload, which the annotations do not express. It still says nothing about pagination behavior or truncation beyond the limit parameter's cap.

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?

Two sentences, zero filler. The scope and field list come first and the move_messages routing pointer second, so the most decision-relevant information is front-loaded.

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 no output schema, the description correctly takes on the burden of describing the return shape (id, subject, sender, received date, read state, no bodies), which is what an agent needs to decide whether a follow-up get_* call is required. The remaining gap is the undocumented folderId source and no clarification of overlap with search_outlook_messages.

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 75%, with mailbox and search well documented in-schema and folderId left bare. The description only gestures at folder scoping ('in one folder') and adds no syntax, format, or lookup path for folderId, so it does not compensate for the gap. Baseline 3 is appropriate when the schema carries most of the burden.

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 ('List messages in one folder') and enumerates the returned fields, which clearly separates it from body-fetching siblings like get_outlook_message. It does not, however, distinguish itself from search_outlook_messages, which by name appears to overlap heavily with this tool's folder-scoped search parameter.

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?

'Use this to get the message IDs that move_messages needs' gives explicit downstream context and names the consuming tool, which is genuinely useful routing information. It stops short of when-not guidance, e.g. it never says whether to prefer this or search_outlook_messages, nor that folderId must first come from list_mail_folders.

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