read_replies

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

The description discloses an important behavioral detail beyond the name: messages are read with BODY.PEEK and remain unread by default, which is useful safety-relevant context given there are no annotations. It does not say what happens when mark_read is true, how the structure 'reply' emails, or mention authentication or failure behavior.

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 compact and front-loaded: the main function, a key behavioral note, and a filter hint are communicated in three short sentences. Nothing is repeated from the schema, and there is no 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?

For a tool with 8 optional parameters and no annotations, the description is not fully self-contained. It omits operational details such as what a 'reply' is, how time-based filtering works besides the concept, and the meaning of selecting mark_read or unread_only. The output schema helps describe the return shape, but selection criteria and behavioral flags remain underspecified.

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?

The schema provides 0% description coverage for the 8 parameters, so the description carries the offset (the below-the-bar context, the bulk of the duty). It adds meaning for from_address and subject_contains, but leaves several meaningful parameters—limit, mailbox, since_hours, unread_only, mark_read, and body_contains—without any prose explanation.

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 first sentence names a concrete action (read), a specific resource (recent reply emails), and a source (IMAP). This is enough to distinguish the tool from the send-oriented and connection-test siblings without opening the schema.

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 implies the tool is for fetching recent replies from an IMAP mailbox and gives concrete narrowing advice with from_address and subject_contains. However, it does not explicitly state when not to use this tool or contrast it with alternatives such as test_imap_connection for connectivity checks.

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