Read Email Message

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

With no annotations supplied, the description carries the full disclosure burden. It does disclose the content returned (headers through body plus a download link), which is the most useful behavioral fact for a read tool, but it says nothing about authentication requirements, whether reading marks the message as read, or error behavior on an invalid mail_id.

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?

A single front-loaded sentence with no filler; the verb and resource lead and the field enumeration follows. The long field list is slightly list-like rather than structured, but every item conveys what the caller gets back.

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?

This is a simple one-parameter read tool with full schema coverage and an output schema, so return values need no explanation in prose. The description covers purpose and content retrieved; only the provenance of mail_id and any side effects of reading are unaddressed, which is a minor gap at this complexity.

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% and the single parameter mail_id is documented with a format example, so the schema does the heavy lifting. The description adds no meaning beyond it, such as where identifiers come from or whether it accepts other ID formats. Baseline 3 is appropriate.

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 uses a specific verb ('Read') and resource ('full email message') and enumerates the returned content (headers, sender, recipients, date, subject, body, download link), which distinguishes it from the list-oriented sibling get_student_emails and the write-oriented send_student_email. It stops short of naming those siblings explicitly, so it's clear but not maximally differentiated.

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?

There is no explicit when-to-use guidance: nothing says this should be called after get_student_emails to fetch a specific message, nor that mail_id must come from a prior listing. The word 'full' hints that this retrieves one complete message rather than a list, but the agent must infer the workflow and the alternative.

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