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

Discloses meaningful behavior beyond annotations: replies arrive in the conversation, daily free-email limits and credit costs apply, and repeat sends are deduplicated unless a new idempotencyKey is supplied. This is consistent with annotations and adds important operational context for a write operation.

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 front-loaded with the core action and remains compact while covering prerequisites, replies, costs, and idempotency. Every sentence adds relevant context for correctly invoking the tool.

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?

Given the absence of an output schema, the description covers the important context an agent needs: prerequisite contact reveal, where replies appear, cost/limit behavior, and idempotent retry semantics. It is complete enough for correct use.

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%, so the schema already documents the parameters well. The description adds useful semantic detail for idempotencyKey and explains that the email goes to the creator’s revealed address, though it does not add much beyond schema for subject, body, or campaignId.

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: sends a plain-text email to a creator’s revealed address. It also distinguishes the tool from siblings by naming reveal_contact and get_conversation, so an agent can tell exactly what this tool does.

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?

Explicitly says to call reveal_contact first before using this tool and points to get_conversation and get_account for related context. This gives clear prerequisites and routing to alternatives instead of leaving usage to inference.

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