gmail_inbox.mark_read

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

With no annotations, the description solely discloses the behavior: removing the UNREAD label. This is accurate for a simple boolean toggle, but it omits idempotency (what if already read?), permission requirements, or consequences for related labels. Adequate but not thorough.

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 at one sentence and front-loads the action. It avoids verbosity, but could be slightly expanded to include parameter hints without losing efficiency.

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 an output schema, the description covers the core action. However, it lacks explanation of return value, edge cases (already read, invalid thread_id), and guidance on the optional user_id parameter. Completeness is adequate but not robust.

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 description does not mention any parameters. Given 0% schema description coverage, the tool relies entirely on this description to explain parameters. The names thread_id and user_id are somewhat self-explanatory, but the description adds no contextual meaning (e.g., format of thread_id, default behavior for user_id).

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 a thread as read') and explains the effect ('removes the UNREAD label'). This distinguishes it from siblings like gmail_archive_thread which moves rather than marks. The verb+resource is specific and unambiguous.

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?

No guidance is provided on when to use this tool versus alternatives like gmail_mark_thread_read or gmail_inbox.archive. There is no mention of prerequisites, thread state expectations, or cases where this tool is inappropriate.

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