gmail_read_thread

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

With no annotations, the description must carry the full burden of behavioral disclosure. It only says 'Read', implying a read-only operation, but adds no detail about side effects, authentication requirements, or whether the thread's state is altered (e.g., marking as read). This adds no value beyond the tool name and does not clarify potential behaviors.

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, clear sentence with no extraneous words. It is front-loaded and efficient, stating exactly the action and object. There is no waste or redundancy.

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 tool is simple, but with no output schema and no description of the return value, the agent cannot know what to expect when calling it. The description also fails to provide any additional context about the thread (e.g., whether it returns all messages or metadata). It is incomplete for successful invocation.

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 description does not mention any parameters or provide additional context for them. The schema covers 'account' but leaves 'threadId' undocumented, and the description fails to compensate for that gap. Since schema coverage is exactly 50% (not high), the description should add meaning for the undocumented parameter, which it does not.

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 states a clear verb ('Read') and a specific resource ('one Gmail thread'), which unambiguously distinguishes it from siblings like gmail_read_message (which reads a single message) and gmail_search (which finds threads). The phrasing also implies a single-thread scope, setting it apart from any batch operations.

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 no guidance on when to use this tool versus alternatives such as gmail_read_message or gmail_search. It does not state explicit conditions for choosing this tool or when to prefer a sibling, leaving the agent to infer based solely on the name.

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