mark_all_read

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

The description complements annotations (idempotentHint=true, destructiveHint=false) by detailing the dryRun preview behavior and the exclusive date constraint. It adds useful behavioral context beyond what annotations provide, though it could mention error handling or performance.

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 front-load the main purpose and key options. Every word is necessary; no fluff or redundancy.

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 simple tool with 3 optional parameters and no output schema, the description covers the essential behavior (marking read, date filtering, dry run). It lacks mention of return value or error cases, but given the tool's low complexity, it is adequate.

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 baseline is 3. The description adds minor value by repeating the dryRun preview and noting the exclusive date format for olderThan, but these are already implied in the schema descriptions. No additional semantics beyond schema.

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 action ('Mark all unread messages in a folder as read') and the scope (all unread messages in a folder, optionally filtered by date). This distinguishes it from sibling tools like bulk_update_flags or update_message_flags by being specifically for the 'mark as read' action on all unread messages in a folder.

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 provides basic usage context (dryRun, date filtering) but does not explicitly state when to use this tool versus alternatives (e.g., for single messages use update_message_flags). It does not include when-not-to-use guidance or comparison with siblings.

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