get_message

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

No annotations are provided, so the description must fully disclose behavioral traits. It states what is returned but does not mention whether the message is marked as read, if there are any side effects, or rate limits. For a read-like operation, the description could be more explicit about its non-destructive nature.

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 that conveys the core purpose without extraneous words. It is well-structured and easily scannable. A slight improvement could be front-loading the return value structure, but it is already efficient.

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 no output schema and 50% parameter description coverage, the description is minimally complete for a simple fetch tool. It states what is returned but does not detail the structure (e.g., format of attachments metadata). Without annotations, it could provide more context about typical usage, but it covers the basics.

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 description coverage is 50% (only uid described). The description does not add extra meaning beyond the schema; it only says 'by UID'. The mailbox parameter is mentioned in schema but its purpose (e.g., which mailbox to fetch from) is not elaborated. This leaves ambiguity for the agent.

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 verb 'Fetch', the resource 'full content of a single message', and the method 'by UID'. It specifies exactly what content is included (text, html, attachments metadata), which distinguishes it from siblings like list_messages (which returns metadata only) and search_messages.

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 does not explicitly state when to use this tool versus alternatives like list_messages (for listing) or search_messages (for searching). While the sibling list implies differentiation, the description lacks explicit usage guidance, such as 'Use this when you need the full message content rather than just the subject/date.'

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