read_mail

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

With no annotations, the description carries the full behavioral disclosure burden. It transparently states the operation, the 1-10 email limit, and the boundary that attachment filenames are listed but file contents are not read. However, it omits the effect of max_body_chars on body truncation, which is relevant given the claim of reading 'full' content.

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?

Two short sentences, front-loaded with the core purpose, followed by a critical negative behavior and the correct alternative. Every sentence earns its place and there is no fluff.

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 tool has an output schema, so return values need not be described. The description covers the operation, input source, count limit, and attachment-handling boundary. The main gap is the undocumented behavior of max_body_chars, but the overall context is sufficient for safe invocation in most cases.

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 0%, so the description must compensate. It usefully clarifies that ids are handles from search_mail and that 1-10 emails are supported, but it says nothing about max_body_chars, its default, or its truncation behavior. The description partially compensates for the missing schema descriptions but not fully.

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 names a specific verb ('Đọc nội dung đầy đủ'), a precise resource (1-10 emails), and a clear source for those emails ('theo handle từ search_mail'). It also distinguishes itself from read_attachment by stating that it only lists attachment names and does not read file contents.

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 clearly states when to use the tool — after search_mail, to read full email content — and explicitly directs the agent to read_attachment for attachment contents. It does not contrast against get_thread or list_folders, so the guidance is strong but not exhaustive across all siblings.

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