list_email_threads

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

No annotations are provided, so the description carries the full burden. The description implies this is a read-only operation (list), which is typical and safe, but it does not explicitly state non-destructiveness. It also does not mention rate limits, pagination behavior (though schema has page/limit), or any side effects. For a listing tool, basic safety is assumed, and the description adds little beyond the schema.

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 very concise, consisting of a single line in Spanish and English. It is front-loaded with the action and resource. However, it could be better structured by separating the core purpose from additional context. The brevity is acceptable for a simple list tool but leaves out important details.

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 tool with 11 parameters, no output schema, and no annotations, the description is insufficient. It does not explain what the list returns (e.g., thread subjects, senders, dates), how pagination works, or any constraints (e.g., maximum results). The schema describes parameters but the description should provide usage context, which is lacking.

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 has 100% description coverage, so the baseline is 3. The description mentions filters by status and account (which correspond to 'filter' and 'account_id' parameters), but it does not describe the other 9 parameters like search, from_filter, has_attachments, etc. The description adds minimal value over the schema descriptions, which already explain each parameter.

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 the tool lists email threads of the store and mentions filters by status and account. It uses specific verb 'list' and resource 'email threads', which distinguishes it from sibling tools like get_email_thread_detail (detail of a single thread) or list_email_accounts (accounts). However, it does not explicitly differentiate from other list tools like list_email_drafts, but the resource name provides clarity.

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?

No guidance is provided on when to use this tool versus alternatives. For example, it does not indicate that list_email_threads is suitable for browsing/filtering threads, while get_email_thread_detail should be used for retrieving details of a specific thread. No exclusion criteria or best practices are mentioned.

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