get_gmail_message_content

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

With no annotations, the description carries the behavioral burden. It clearly signals a read operation via 'Retrieves' and describes the returned fields, which is useful. However, it omits prerequisites like prior authentication, error behavior for invalid IDs, and limitations such as plain-text-only body or absence of attachments.

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 compact and well-organized, with a front-loaded purpose sentence followed by Args and Returns sections. It adds useful return details like date and Message-ID. There is minor overlap between the opening sentence and the Returns section, but this does not hurt clarity.

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 two-parameter, read-only tool with no nested objects and an output schema present, the description covers the core essentials: what the tool does, both parameters, and the return content. The main gaps are lack of explicit routing among many similar Gmail siblings and any authentication prerequisite, but these are modest given the tool's low complexity.

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 input schema has 0% parameter description coverage, so the Args section is essential and provides at least a one-line explanation for both parameters. 'message_id' is described meaningfully as the unique ID of the message to retrieve, and 'user_google_email' clarifies it is the user's email and required. The descriptions are minimal but compensate for the schema's lack of detail.

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 opens with a specific verb ('Retrieves'), names the exact resource ('a specific Gmail message'), and enumerates the content scope (subject, sender, recipients, plain text body). This clearly distinguishes the tool from search, batch, and thread-related siblings, even without naming them.

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 usage is implied: use this tool for retrieving the full content of a single Gmail message. However, it does not explicitly mention alternatives or exclusions, such as 'use get_gmail_messages_content_batch for multiple messages' or 'use get_gmail_thread_content for a whole thread.' An agent must infer routing from sibling names and the word 'specific.'

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