batch-mark-as-read

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

With no annotations, the description carries the full burden and discloses return values ('counts of how many were marked read and how many failed') and an important edge case ('an id that matches in several mailboxes is refused, not guessed'). It does not mention idempotency or auth, but the core behavioral traits are covered.

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 well-structured with labeled sections ('Use when', 'Returns', 'Do not use when') and a concise final instruction. Every sentence serves a purpose without unnecessary padding or repetition.

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 parameter count and output schema, the description provides complete contextual guidance: usage conditions, alternatives, return counts, prerequisites, and ambiguous-id handling. It is sufficient for an agent to select and invoke the tool correctly.

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 schema lacks a description for the 'ids' parameter and only partially covers sourceAccount/sourceMailbox. The description adds essential meaning by explaining that ids come from search-messages/list-messages and clarifying that sourceMailbox/sourceAccount is needed to pin numeric ids to a specific mailbox.

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 explicitly states the verb and resource: 'marking multiple messages (1–100 ids) as read in one call.' It also distinguishes itself from siblings by naming 'mark-as-read' for single messages and 'batch-mark-as-unread' for unread.

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 includes explicit 'Use when' and 'Do not use when' clauses with alternative tool names, and provides a clear prerequisite: 'Get the ids from search-messages or list-messages first.' It also explains the sourceMailbox/sourceAccount requirement.

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