Check messages

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

With no annotations, the description carries the full burden, and it does disclose several non-obvious behaviors: blocking semantics for wait, the unread-message definition (header-delivered messages excluded), and what happens when nothing new exists (recently received ones are 'noted for reference'). It leaves unclear whether fetching marks messages as read, and does not describe message shape or size limits, which matters for a receive tool.

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?

Three short sentences, purpose front-loaded, then wait behavior, then the unread edge case. No restatement of the name, no filler, and each sentence conveys something an agent could act on.

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?

With no output schema and no annotations, the description supplies the return semantics an agent needs (unread-only, fallback of recent messages, blocking behavior). Remaining gaps — whether reads are consumed, and what a message looks like — are modest for a simple polling endpoint but would be worth one clause.

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 all three parameters are well documented in the schema itself (including the wait-vs-polling hint and the slot port arithmetic). The description adds only the conversational framing of wait ('for real-time conversation'), so the baseline 3 applies — the schema, not the description, does the parameter work.

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: 'Shows your unread messages.' It also clarifies a non-obvious boundary (messages delivered in another tool's header are not unread), which lets an agent reason about what it will get back. It does not name a sibling alternative (slot_send) or reference slot_pause/slot_resume, so differentiation comes mostly from the distinctive 'inbox' concept rather than explicit routing.

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 explains the polling mode ('with wait, waits up to that long for a new message (for real-time conversation)'), which is real guidance, but usage conditions are only implied — there is no explicit 'use this when X, use slot_send when Y' statement or statement of when not to call it. The agent must infer that this is the receive half of a send/receive pair.

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