Find emails waiting for your reply

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

Annotations already declare readOnly/openWorld/non-destructive, so the safety profile is covered. The description adds real value beyond that: default scope across all accounts, exclusion of newsletters/notifications/no-reply senders, oldest-waiting-first ordering, and the fact that draft status is surfaced per conversation. It doesn't mention limits or result-volume behavior, keeping it below a 5.

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?

Three tight sentences with the core predicate and default scope front-loaded, followed by exclusions and use cases. The example intent queries are slightly redundant with the opening sentence but still earn their place as routing cues.

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 five-optional-parameter, read-only query tool with full schema coverage and no output schema, the description covers the selection criteria, defaults, exclusions, ordering, and one key return signal (existing draft). Nothing an agent needs to call it correctly is missing.

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%, so all five parameters are already documented with defaults and bounds. The description reinforces the account default ('ALL accounts') and the automated-sender filtering but adds no syntax or format detail beyond the schema; baseline 3 is appropriate.

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 states a specific verb ('Find conversations'), a precise resource and filter predicate (someone else wrote last, you haven't answered), and a default scope (ALL accounts). It is clearly distinguishable from siblings like search_emails or inbox_summary, which don't encode the reply-pending criterion.

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?

It gives concrete user-intent phrasings ('who am I supposed to get back to?', 'what's waiting on me?') that map directly to invocation, and states the default all-accounts behavior. It does not name an alternative sibling or state when NOT to use it, so it falls short of a 5.

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