update-mail-message

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

Annotations indicate destructive behavior (destructiveHint=true) and mutation (readOnlyHint=false). The description adds no additional behavioral context beyond the schema, such as permissions required, side effects, or response details.

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 a single sentence, but it lacks critical details (e.g., scope, what an eventMessage is). It is under-specified rather than appropriately concise.

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 complexity of the input schema (nested objects, many properties) and lack of output schema, the description fails to explain the tool's purpose for event messages, prerequisites, or which properties are mutable. It is insufficient for an agent to use correctly.

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 75%, so baseline is 3. The description adds no extra meaning to parameters; it does not highlight which fields are updatable or mention required parameters beyond what schema already shows.

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 states it updates an eventMessage object, but the tool name is 'update-mail-message', creating ambiguity about whether it applies to all mail messages or only event messages. No differentiation from siblings like 'create-draft-email' or 'update-mail-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?

No guidance on when to use this tool vs alternatives (e.g., create-draft-email for new messages, update-mail-folder for folder properties). No prerequisites or context provided.

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