check_replies

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

No annotations are provided, so the description carries the full burden. It does disclose a useful data-model detail (replies are entries of type="reply" in one's own inbox, evaluated separately from normal messages), but says nothing about read-only semantics, permissions, or scope. For a zero-parameter read tool this is adequate but thin.

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 compact sentences, front-loaded with the core purpose and followed by the mechanism. Nothing is padded, though the second sentence is slightly redundant with the first.

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?

An output schema exists, so return-value explanation is not required. For a parameterless read-only check, the description plus schema is nearly sufficient; only the absence of any behavioral constraints keeps it short of full completeness.

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 tool takes no parameters, so the baseline is 4; the description adds the relevant conceptual context that results come from the caller's own inbox rather than an arbitrary target.

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?

States a specific verb and resource: checking whether replies arrived for one's own sent messages. It also distinguishes itself from normal inbox reading by noting replies are evaluated separately, which differentiates it from the check_inbox sibling, though it does not name that sibling explicitly.

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?

Usage is implied — use this to see reply status rather than general messages — but there is no explicit when-to-use statement, no named alternative (check_inbox), and no guidance on ordering relative to send_message or reply.

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