Send Inbox Reply

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

Annotations already declare destructiveHint=true and openWorldHint=true, so the safety profile is partly covered. The description adds meaningful context: it emphasizes this is a REAL SEND, requires an explicit user_authorized confirmation, and mentions the idempotency key for retries. That adds value beyond the annotations, even though it does not disclose rate limits or exact post-send 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 a single front-loaded sentence with zero wasted words. 'REAL SEND' immediately sets the tone, and the rest of the sentence delivers the essential constraints.

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 an 8-parameter destructive real-send tool with no output schema and only 25% schema description coverage, the description is too sparse. It covers the user-authorization and idempotency safety aspects but does not document most parameters, expected behavior on success or failure, or how to choose this tool over alternatives.

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 only 25%, so the description should compensate for undocumented parameters. It only references idempotency_key and send_confirmation (which are already described in the schema) and gives no meaning for platform, thread_id, subject, body_text, attachments, or campaign_creator_id. Six of eight parameters remain unexplained by either schema descriptions or the tool description.

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 and resource: 'send one user-authorized reply to a Hyperstar inbox thread'. This clearly distinguishes a real send from sibling read/update operations like get_inbox_thread_messages or update_inbox_thread_state, though it does not name those alternatives explicitly.

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?

Usage is implied by the phrase 'REAL SEND' and the requirement for explicit user authorization, which signals this is only for actual approved sends. However, the description does not state when to use this versus alternatives, nor does it give explicit exclusions or prerequisites beyond the authorization phrase.

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