Update Inbox Message

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

Annotations already indicate idempotentHint=true and destructiveHint=false, so the description's statement about setting read/starred states adds some value beyond structured data. No contradictions; behavioral disclosure is adequate but not enriched further.

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 concise sentences with no redundant information. It front-loads the core purpose and adds a usage hint efficiently.

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 output schema exists, parameters are fully documented in schema, and annotations are present, the description provides sufficient context for an agent to use the tool correctly. It lacks only minor details like side effects or return value hints, but overall 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?

Schema coverage is 100%, so the description does not need to add parameter details. The description mentions 'read and/or starred state' which maps to two boolean parameters, but this is implicit. Baseline 3 is appropriate.

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 'Set read and/or starred state on one inbox message,' specifying the action and resource. It distinguishes from sibling tools like move or delete by focusing on state updates and requiring an exact message ID.

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 the usage condition 'Use only when the operator has identified the exact message ID,' providing clear context. However, it does not explicitly state when not to use or mention alternatives among siblings, slightly limiting guidance.

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