search_threads

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

No annotations provided, so description carries full burden. Explains return structure and how threading works for Gmail vs IMAP. Does not explicitly state that the operation is read-only, but the context implies it. Good but could mention safety.

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?

Two concise and front-loaded sentences. First sentence states core function, second adds return details and usage advice. No extraneous information.

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?

Output schema exists but not described. The description provides return structure details. However, it omits order, pagination behavior, and handling of limit parameter. Given the complexity, slightly incomplete.

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?

Schema description coverage is 0%, meaning no parameter descriptions. The description only mentions 'matching the filters' generically, without explaining any of the 7 parameters (account, folder, query, senders, etc.). This is insufficient for correct invocation.

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?

Clearly states it lists conversations (threads), not individual messages. Distinguishes from sibling tools like list_emails or search_emails_by_sender. Describes return format: one entry per thread with latest message metadata and message_count.

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?

Explicitly advises using this tool when the user asks 'who has been discussing X?' and wants to avoid seeing many duplicates of a reply chain. This guides the agent on appropriate context compared to message-level tools.

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