list-mail-folder-messages

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds only that the tool supports both listing and searching, but does not disclose pagination behavior, cursor semantics, or OData/KQL filtering traits, which are left to the parameter schema.

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 a single sentence with no wasted words. Action and scope are front-loaded, allowing an agent to quickly understand the tool's purpose without digging through the schema.

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?

Despite a rich schema, the tool description is minimal for a 10-parameter operation. It omits the pagination contract, the full-text search and OData filter capabilities, and does not clarify how this tool differs from shared-mailbox or top-level mail listing siblings. The schema and annotations cover invocation details, but the description leaves selection ambiguity among closely related tools.

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 every parameter carries a meaningful description. The tool description merely echoes 'search' capability that already exists in the search/filter parameters, adding no value beyond the schema. Baseline 3 is appropriate.

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 clear action ('List/search') and a specific resource scope ('messages inside a specific mail folder'). This distinguishes it from broader siblings like list-mail-messages, which operate on the whole mailbox, and aligns with the required folderId 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?

The scope of 'specific mail folder' implies when to use it, but there is no explicit guidance contrasting it with alternatives such as list-mail-messages or list-shared-mailbox-folder-messages. An agent must infer the intended context rather than being told directly.

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