Read the full content of a specific email message including sender, recipients, subject, body text, and attachment info.
| Name | Required | Description | Default |
|---|---|---|---|
| address | Yes | The inbox email address (e.g. abc123@myagentinbox.com) | |
| message_id | Yes | The message ID from check_inbox results |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, confirming a safe read operation. The description adds value by specifying exactly what content is returned (sender, recipients, subject, body, attachment info), which is useful beyond the annotations. No contradiction exists.
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, well-structured sentence that front-loads the verb and resource, then lists what is included. Every word earns its place; 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 read operation with robust schema and annotations, the description is complete: it tells the agent what the tool does, what it returns, and how to reference a message. The absence of an output schema is compensated by the clear list of return fields. Sibling tools are implicitly known from context.
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 100%, so both parameters are already adequately documented (address as inbox email, message_id from check_inbox results). The description adds minimal extra meaning beyond what the schema provides; it mentions returned content but does not clarify parameter formats or constraints.
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 specific verb 'read' and resource 'email message', and enumerates the content fields returned (sender, recipients, subject, body text, attachment info). This distinguishes it from sibling tools like check_inbox (which lists messages) and download_attachment (which fetches a single attachment).
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 implies the use case: retrieving the full content of a specific email message. The schema parameter 'message_id' explicitly references 'check_inbox results', providing context for when to use this tool. However, the description itself does not explicitly name or exclude alternatives it lacks an explicit 'when not to use' statement.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct action: creating an inbox, checking for messages, reading a specific message, and downloading an attachment. There is no functional overlap between them.
All tool names follow the verb_noun pattern in snake_case (check_inbox, create_inbox, download_attachment, read_message), which is perfectly consistent and predictable.
Four tools is well-scoped for a disposable email service, covering the essential operations without unnecessary bloat or missing functionality.
The tool set covers the full lifecycle of a disposable inbox: creating it, checking messages, reading details, and handling attachments. Since inboxes auto-expire, no delete tool is needed, so there are no obvious gaps.
