Check messages

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

With no annotations and no output schema, the description carries the full burden and does add real behavioral detail: the deduplication rule ('messages already delivered in another tool's header are not unread') and the fallback when nothing is new ('recently received ones are noted for reference'). It stops short of describing return shape or auth/identity implications of the agent parameter.

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 sentences, front-loaded with what the tool returns before the wait semantics and the unread-definition caveat. Dense but each sentence carries information; minor awkwardness in the final clause.

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 3-parameter messaging tool with no annotations and no output schema, the description covers the unread/wait semantics but never says what the returned messages actually look like or who sent them. It is adequate to invoke correctly but leaves the response shape to be discovered.

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%, so the schema already documents slot, wait, and agent in detail — including the wait anti-polling rationale. The description's mention of wait largely restates the schema, adding no syntax or format beyond it; baseline 3 applies.

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'), making it immediately clear this is the receive side of the inter-agent messaging pair with slot_send. It does not explicitly name slot_send as the counterpart, so sibling differentiation relies on inference from the resource noun.

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?

Gives clear context for the distinguishing parameter: use wait for real-time conversation, letting the agent block instead of polling. There are no explicit exclusions or named alternatives, but no alternative receive tool exists in the sibling list, so the missing 'when not to use' costs little.

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