get_email_thread

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

With no annotations provided, the description carries the full burden. It discloses that each message includes attachment metadata (filename, attachment_id, size) and that content is not included, pointing to get_all_attachments. This gives a clear expectation of what the tool returns and what it doesn't.

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 two sentences, front-loaded with the main action, and directly communicates the core function and a cross-reference. No fluff or redundant phrases.

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 tool's main purpose, the key output details, and a related next step for attachment content. Given no output schema, it compensates by explicitly stating what appears in each message.

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?

Both parameters are already well-described in the schema (100% coverage), so the description adds little beyond reinforcing that account is required. The description adds context about the output (Gmail ID) but not about the input semantics.

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 'Get a full email thread for one account,' which is a specific verb+resource and clearly distinguishes this from sibling tools like read_emails or search_emails. It also contextualizes the output with attachment metadata.

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 notes 'account required' and clarifies that to read attachment content, the user should call get_all_attachments, providing an explicit alternative. It doesn't explicitly mention when not to use this tool vs other email tools, but the context is clear.

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