mark_as_read

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

Annotations are absent, so the description carries the full behavioral burden. It discloses only the intended state change and nothing about idempotency, reversibility, permissions, or response behavior. This is minimal but not misleading.

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?

A single short sentence with no filler or redundant clauses. It states the verb and object clearly in the first few words.

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 with complete schema coverage, the core invocation is clear. However, without annotations or an output schema, the description leaves side effects, return value, and failure behavior unspecified; adequate for a basic call, but not fully complete.

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 covers both parameters (uid and mailbox) with 100% coverage, and the mailbox description already explains UID uniqueness. The tool description adds no parameter-level semantics beyond the 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?

States a specific, unambiguous action ('Mark an email as read') and clearly contrasts with sibling mark_as_unread, star_email, and delete_email. An agent knows exactly what state change this performs.

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 when-to-use guidance is provided. It doesn't say to prefer this over mark_as_unread or explain the conditions under which it should be used; an agent must infer usage from the tool name and context.

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