readGmailThread

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

There are no annotations, so the description must carry the transparency burden. It discloses that output is readable content and metadata is stripped, but does not mention read-only safety, auth requirements, or whether messages are marked as read. This is moderately useful but leaves behavioral gaps.

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 entire description is a single concise sentence that front-loads the action and resource. It contains no filler or redundant phrasing.

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 simple read tool with a well-documented 2-parameter schema, the description adequately conveys the core purpose and output style. However, without an output schema, it only vaguely specifies the return content and does not describe overall response structure, leaving a minor gap.

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 already documents both threadId and includeAttachments with descriptions, so schema coverage is 100%. The description adds no parameter-specific detail beyond what the schema provides, so baseline 3 applies.

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 uses 'Retrieves' as a specific verb, identifies the resource as a complete email thread/conversation, and specifies the output is readable message content stripped of metadata. This clearly distinguishes it from siblings like listGmailThreads or sendGmailEmail.

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 this is for reading full thread content, but it does not explicitly contrast with listGmailThreads or state when not to use it. No clear exclusions or alternatives are provided, so the guidance is only implicit.

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