gmail_message_read

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

No annotations are provided, so the description bears full behavioral disclosure responsibility. It discloses read-only nature, the side effect of writing to a file when output_file is set, and default format behavior. However, it doesn't mention authentication requirements or error handling (e.g., nonexistent ID). The statement 'Mirrors `omni-dev gmail read`' adds little to agent understanding.

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 concise paragraph that front-loads the tool's core function and then details format options. It includes a redundant 'Mirrors `omni-dev gmail read`' stating the obvious and the phrase 'Gmail's own wire values' adds little. Slightly verbose but mostly efficient.

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?

The description covers the essential behaviors: format options with defaults, output_file side effect (writing to disk and changing return), and account selection. It lacks details on error handling, authentication, or the exact return structure when no output_file is used, but the schema and tool name cover most expectations. For a read tool, this is fairly complete.

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 fully documents all four parameters (100% coverage), so the baseline is 3. The description adds value by elaborating on format defaults and the purpose of output_file for large messages, but most semantic detail is already in the schema. It adds marginal but non-essential guidance 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?

The description clearly states 'Read a single Gmail message by id', specifying the verb (read), resource (Gmail message), and the identifier ('by id'). It distinguishes itself from search/thread tools by focusing on a single message. However, it doesn't explicitly differentiate from sibling tools like gmail_thread_read beyond the singular nature, which is implicit but sufficient.

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 provides some usage context, such as when to use 'output_file' (to avoid exceeding context window with attachments) and how the 'account' parameter selects via 'gmail_account_list'. However, it lacks explicit guidance on when to choose this tool over alternatives like gmail_search or gmail_thread_read, and doesn't mention prerequisites like authentication.

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