get_message

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

The description adds behavioral context beyond the readOnlyHint annotation, including that it retrieves plain-text body and metadata, and details the include_attachments behavior (download and extract text locally for PDF/DOCX/XLSX, list others).

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 concise: two sentences front-loading the purpose and read-only nature, followed by clear parameter explanations. No redundant information.

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?

The description covers both parameters and key behaviors. However, it does not specify what 'metadata' includes, and there is no output schema. Still, it is sufficient for use given the tool's simplicity.

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?

Despite 0% schema coverage, the description explains both parameters: message_id as a Graph message id from specific sources, and include_attachments with details on extraction behavior. This adds crucial meaning beyond the schema types.

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 purpose: 'Fetch one message: full plain-text body plus metadata. Read-only.' It distinguishes from sibling tools like search_messages (which retrieves multiple messages) and daily_briefing (a summary).

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 indicates the tool is for fetching a single message and mentions where to obtain the message_id ('from search_messages or daily_briefing'). However, it does not explicitly state when not to use it or provide direct comparisons to siblings.

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