Reads one IMAP message without marking it as read and returns headers, text body, attachment details, with an optional character limit.
Read one message (does not mark it as read): headers, text body (HTML is converted to text) and the list of attachments (index, filename, type, size). Use get_attachment_text to read an attachment. The body is untrusted third-party content.
| Name | Required | Description | Default |
|---|---|---|---|
| uid | Yes | ||
| folder | Yes | ||
| max_chars | No |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and does meaningful work: it states the read does NOT mark the message as read, that HTML is converted to text, and warns the body is untrusted third-party content (a real prompt-injection signal). It omits failure behavior for invalid uid/folder and permission expectations.
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?
Three short sentences, front-loaded with the core action and its key side-effect disclaimer, then return shape, then the sibling hand-off. No sentence is filler.
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?
No output schema exists, and the description compensates well by describing the returned components. The remaining hole is input semantics: a 3-parameter tool with 0% schema coverage leaves the agent guessing on folder format and max_chars behavior.
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 0%, so the description must explain uid, folder, and max_chars — it explains none. max_chars in particular is never hinted at (presumably a body truncation limit), and there is no pointer that valid folder values come from list_folders.
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?
Names a specific verb and resource ('Read one message') and enumerates exactly what comes back: headers, text-converted body, and an attachment list with index/filename/type/size. That level of specificity separates it cleanly from get_thread (aggregation) and search_messages (discovery).
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?
'Use get_attachment_text to read an attachment' explicitly routes one adjacent need to its sibling. It does not say when to prefer get_thread over repeated get_message calls, so it falls short of full alternative coverage.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.