bulk_flag

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

Annotations already indicate mutation (non-read-only, non-destructive). The description adds useful context about the batch process (querying the Envelope Index, single batched AppleScript call), giving the agent insight into how the operation works. No contradictions 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?

Two concise sentences with no unnecessary words. The key information is front-loaded, covering purpose, scope, and mechanism. Every sentence adds value.

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 lack of output schema and the tool's complexity, the description provides a good high-level picture. It explains the filtering and batch update process. It could arguably mention return behavior (e.g., number of messages affected) or error handling, but it's sufficient for a bulk operation tool with high schema coverage.

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 the description doesn't need to explain parameters. The description adds minimal extra meaning by grouping 'mailbox' and 'from' as filtering options, but this is already implied by the schema descriptions. 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 clearly states the tool flags or unflags multiple messages, using verbs 'Flag or unflag' and resource 'multiple messages'. It distinguishes from sibling tools that perform other bulk actions (move, trash, etc.) and specifies filtering criteria.

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 explains when to use the tool (by mailbox, sender substring, or both) and briefly mentions the underlying process. It doesn't explicitly state when not to use it or name alternatives, but the context from sibling names and the bulk nature make the usage reasonably clear.

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