Inbox Triage

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

The description adds minimal behavioral context beyond annotations. Annotations already indicate readOnlyHint=true, destructiveHint=false, idempotentHint=true, so the agent knows it's a safe read operation. The description confirms the read-only behavior ('check', 'list') but does not elaborate on any additional traits. No contradiction with 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?

The description is extremely concise with a single sentence that front-loads the key action. Every word is useful, and there is no redundancy or unnecessary detail.

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?

Given the tool's simplicity (no parameters, no output schema, and comprehensive annotations), the description is complete enough for an agent to understand what the tool does. It could optionally mention the output format (e.g., a list of messages), but the current text is sufficient for triage usage.

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 zero parameters, so schema description coverage is 100%. The description does not need to explain parameters. A baseline score of 4 is appropriate as no parameter information is missing.

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's purpose: 'Check unread mail count and list recent messages for triage.' It uses specific verbs ('check', 'list') and identifies the resources ('unread mail', 'recent messages') and the context ('triage'). There are no sibling tools with similar functionality, so no differentiation is needed.

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 implies usage for triage (initial checking), but it does not explicitly specify when to use this tool versus alternatives or when not to use it. Given the simple read-only nature, the guidance is adequate but could be more explicit by mentioning that it is for quick overview before detailed actions.

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