read_email

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

With no annotations provided, the description carries the full burden of behavioral disclosure. The verb 'read' implies a safe, non-mutating operation, but no explicit statement about side effects, authorization requirements, or error behavior is made. The description is adequate for a simple read tool but does not add rich context beyond what 'read' naturally conveys.

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, well-structured sentence with no wasted words. It is front-loaded with the action and resource, making it easy to scan. Absolutely minimal and effective.

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?

For a tool with only one parameter and no output schema, the description sufficiently covers the core function: fetching full email content by UID. It could be enhanced by clarifying what 'full content' includes (e.g., headers, body, attachments), but given the simplicity and clear parameter, it is nearly complete. Sibling tools and annotations would normally fill remaining gaps, but none are present here.

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?

The schema already provides 100% coverage for the single parameter 'uid' with description 'Email UID'. The tool description repeats 'by UID' but adds no additional semantic detail beyond what the schema already provides. Since schema coverage is high, this is a baseline 3; no extra value is contributed.

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 clearly states the tool's function: 'Read full email content by UID'. It specifies a concrete verb (read), a specific resource (email content), and a key targeting mechanism (UID), which distinguishes it from siblings like search_emails (search-based) or get_recent (list recent). The purpose is unambiguous and immediately actionable.

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 description implies the usage context: when you have a UID and need the full email body, this is the tool to use. It does not explicitly state when not to use it or mention alternatives such as get_attachment or get_recent, but the UID-based targeting provides clear context. This is more than a vague hint but lacks explicit exclusions.

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