mark_as_read

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It notes that UIDs are permanent identifiers, which gives some context about the stability of references, but it does not disclose side effects, reversibility, idempotency, or permission requirements. As a mutation tool, this is a significant gap.

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 two short sentences with no filler. The first sentence states the action and method; the second provides a brief auxiliary note about UIDs. Both sentences earn their place, and the structure is front-loaded with the core purpose.

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 mutation tool with no output schema and no annotations, the description is thin but adequate. The schema covers all parameters, and the tool's operation is straightforward. However, it lacks usage context and behavioral details like idempotency or folder handling beyond the schema, leaving some gaps for an agent.

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 input schema already fully describes both parameters (uids and folder) with default values and coverage 100%. The description adds a note that UIDs are permanent, which reinforces the semantics of the uids parameter but does not provide substantial new information. Baseline 3 is appropriate when schema covers the parameters.

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's action ('Mark emails as read') with a specific method ('using UIDs'). It distinguishes from sibling tools like mark_as_unread by the explicit action, though it does not name alternatives. The phrase 'UIDs are permanent identifiers' adds useful context about the identifier mechanism.

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?

There is no guidance on when to use this tool versus alternatives such as mark_as_unread, flag_emails, or archive_emails. The description only states what the tool does, leaving the decision of when to invoke it entirely to the user. No exclusions or contextual hints are provided.

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