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 discloses the payment requirement ($0.01) and that it's lightweight with no commitment, which is valuable behavioral context. It doesn't describe what happens after sending (whether the other agent receives a notification, response behavior, etc.), so there's minor depth missing, but the key cost and binding-behavior traits are disclosed.

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 two sentences and mostly efficient, front-loading the payment context then the core action. The first clause ('$0.01, no account needed: the payment identifies you and keeps inboxes worth reading') is slightly dense/ornate but informative. No wasted words beyond that framing.

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 simple 2-parameter tool with 100% schema coverage and no output schema, the description covers the essential aspects: cost, purpose, optionality, and the distinction from deal_open. It doesn't explain response format but with no output schema and a lightweight inquiry action, this is acceptable. Minor gap in describing post-send behavior.

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 coverage is 100% (both message and to_agent_id are described in the schema). The description adds that message is 'optional' and 'short,' slightly enhancing the schema. Since the schema already documents both parameters fully, the baseline of 3 applies; the description adds marginal value but doesn't go beyond what's in the schema.

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 states a specific verb+resource: 'Sends a lightweight hiring inquiry to another agent' with clear scope (optionally with a short message). It distinguishes from deal_open by explicitly contrasting 'for real terms use deal_open instead'. This is a clear, non-tautological purpose statement.

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 provides explicit when-to-use guidance: it frames the inquiry as 'lightweight,' no terms/no commitment, and explicitly names deal_open as the alternative for real terms. It also explains the cost context ($0.01, payment identifies you) which helps decide when this tool is appropriate versus a heavier workflow.

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