gmail_threads_modify

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

The description explains the effects of actions (e.g., 'remove INBOX' to archive, 'remove UNREAD' to mark read) and aligns with the readOnlyHint=false annotation. No contradictions; it adds context beyond annotations.

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 sentences, front-loaded with purpose, followed by key examples. No unnecessary words; every sentence earns its place.

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 all essential use cases for a modification tool, but lacks information about prerequisites (e.g., OAuth scopes) or error handling. Since there is no output schema, return values are not explained, but that is acceptable for a mutation tool.

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 coverage is 100%, and the description adds semantic value by showing how to use addLabelIds and removeLabelIds with common label identifiers (STARRED, INBOX, UNREAD), making it easier for the agent to select correct parameter values.

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 action: 'Modify a Gmail thread: add/remove labels' and provides specific examples (archive, mark read, star) that distinguish it from sibling tools like gmail_threads_get or gmail_threads_list.

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 gives concrete use cases (archive, mark read, star) but does not explicitly state when not to use the tool or mention alternatives for other modifications (e.g., deleting). Still, the examples are practical and cover common scenarios.

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