mailbox_check

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

The description discloses a significant side effect: fetched messages 'become acked.' This goes beyond what the name alone implies. However, it does not explain what 'acked' means in practice, whether the effect is reversible, or how the mark parameter influences this 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 one tight sentence with a parenthetical, front-loading the core action before the side effect and usage timing. Every phrase earns its place, 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?

With no annotations, no output schema, and no parameter descriptions, the single sentence leaves important gaps: what 'acked' means for message availability, the role of mark and agent_id, and how this differs from mailbox_list. An agent can begin to use it but lacks enough context to invoke it with full confidence.

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 carries the full responsibility for explaining parameters, but it mentions neither 'mark' nor 'agent_id.' The parenthetical about messages becoming acked hints at mark's behavior but never names the parameter or clarifies the default true value.

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 clearly states a specific action ('Fetch your pending messages') and identifies the resource ('messages'), so an agent can tell this tool retrieves mailbox contents. However, it does not differentiate this tool from the sibling mailbox_list, which likely also relates to reading messages.

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 explicitly says 'Call at session start,' giving a clear contextual trigger for when to use this tool. It does not mention alternatives or when not to use it, but the timing guidance is concrete and useful.

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