label_message

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

No annotations provided. Description only states the action, but does not disclose permissions, side effects, reversibility, or rate limits. For a mutation tool, more context is needed.

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?

Single sentence, front-loaded, no wasted words. Efficiency is excellent.

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?

Tool is simple but lacks essential details like prerequisites, return values, and whether labels are additive. Without annotations, the description is insufficient for complete understanding.

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 67% (messageId lacks description). Description does not add semantic meaning beyond the schema, failing to compensate for missing parameter documentation.

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?

Description clearly states verb 'Add labels' and resource 'single message', with context 'Multi-account Gmail'. It distinguishes from sibling tools like label_thread and unlabel_message.

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?

Implied usage: for labeling a single message, not a thread. No explicit when-to-use or alternatives, but the context of sibling tools provides some differentiation.

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