Retrieve the full original MIME source of an email, including headers and all parts, to inspect raw content or forward the message intact.
Get the full original MIME source of an email (headers + all parts).
| Name | Required | Description | Default |
|---|---|---|---|
| messageId | Yes | Message ID (from zoho_list_emails / zoho_search_emails). Pass as a string — Zoho IDs are 64-bit and lose precision as JSON numbers. |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a genuinely useful behavioral detail: the return is the full raw MIME source rather than parsed fields. It does not mention size limits, binary/attachment handling, or encoding, which are relevant for a MIME dump.
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?
One sentence, front-loaded with the verb and resource, with the scope clarification packed into a parenthetical. No filler or redundancy.
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 single-parameter read tool with full schema coverage and annotations, the description is nearly sufficient, and its scope note partially compensates for the absent output schema by stating what the payload contains. It stops short of addressing practical concerns like large messages or attachment parts.
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% and the single messageId parameter is thoroughly documented in the schema (string, pattern, precision warning, source of the ID). The description adds nothing beyond the schema, so the baseline 3 applies.
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 verb ('Get') and resource ('original MIME source of an email') with a clarifying parenthetical that scopes the output to 'headers + all parts'. This implicitly separates it from the headers-only and body-only siblings, but it never names those siblings explicitly, so it falls short of full differentiation.
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 gives no when-to-use guidance, no prerequisites, and no alternative tool to choose instead. An agent must infer that raw MIME is wanted rather than the parsed content from zoho_get_email_content or zoho_get_email_headers; nothing in the text tells it which to pick.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.