read-email

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

Annotations already provide readOnlyHint=true, and the description adds extensive behavioral detail: default output fields, behavior of headersMode and related parameters, output formatting (Markdown vs JSON), and verbosity control. No contradictions with annotations.

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 relatively long but efficiently packs many mode combinations and output details. It front-loads the primary purpose and progresses logically, though some repetition could be trimmed.

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?

No output schema exists, but the description fully covers return values: full message body (HTML stripped), subject, from/to/cc, receivedDateTime, conversationId, attachments metadata, webLink, and details for headersMode and outputVerbosity options. All parameters and interactions are explained.

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 100%, but the description significantly enriches parameter meaning by explaining combinations and output effects, e.g., 'pair with importantOnly: true for the security-relevant subset' and 'groupByType: true for category-bucketed view'. This goes well beyond the schema descriptions.

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?

Description clearly states 'Read a single email by id (read-only)', specifying the exact action and resource. It distinguishes from sibling tools like 'search-emails' and 'send-email' through its focused scope.

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 explicit guidance on when to use this tool versus alternatives like search-emails. While the purpose is clear, the description does not provide exclusion criteria or recommend when to prefer this tool for single email reads.

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