Read email

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

readOnlyHint=true already establishes this is a safe read, so the bar is lower. The description usefully discloses the return content (headers + body), but says nothing about a mark-as-read side effect (email_mark_read exists as a sibling), folder semantics, or auth/rate-limit constraints.

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?

A single front-loaded sentence with no filler; the resource, scope, and return payload are all in the first clause. Nothing to trim.

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 deserves credit for naming the returned payload, and the required UID is clear. However, the folder/server targeting behavior and any read/unread side effect are left unaddressed, leaving gaps for a 3-parameter tool in a dense mail family.

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?

Two of three parameters are documented in the schema and the description reinforces 'by UID'. The folder parameter has only a default and the description never explains what changing it does, so it neither fills the remaining 33% coverage gap nor adds syntax beyond the schema.

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 (Read) and resource (a single email), and the qualifier 'by UID' plus '(headers + body)' distinguishes it from list/search siblings like email_list and email_search. It stops short of naming an alternative explicitly, but the singular/single-message scope is unambiguous.

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?

No when-to-use guidance or prerequisites. It does not tell the agent to use email_search or email_list first to obtain a UID, nor when to prefer this over email_filter_list, so selection among the read-family siblings is left to inference.

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