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

Goes well beyond the annotations (readOnly=false, openWorld=true, destructive=false) by disclosing that it cannot open conversations or carry attachments, that each call is confirmed by default and that this can be toggled, that the message reaches other people requiring user confirmation, and that a scoped Cotlet API key is required. This is a rich behavioral profile an agent needs before sending.

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 purpose is front-loaded and most sentences earn their place, but the opening two sentences restate the same idea ('send a message as your brand in an existing conversation' vs 'sends a text message in an existing conversation, under your brand name'), which is mild redundancy.

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 two-parameter mutation with no output schema, the description covers the important gaps: scope limits, attachment handling, confirmation semantics, human-impact warning, and auth requirements. An agent has everything needed to call it correctly.

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 both body and conversation_id are already documented, including that conversation_id comes from list_conversations. The description adds only identity framing ('under your brand name') and no format or constraint details, so the baseline 3 is appropriate.

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 (send) and resource (message in an existing conversation) and pins the identity context (as your brand, with a retailer). It distinguishes itself from siblings like faire_send_campaign by restricting to existing conversations, so an agent can select it without opening the schema.

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 states when-not-to-use: it cannot start a conversation and cannot attach files, routing attachments to the desktop portal. It also flags the per-call confirmation behavior and the need to confirm with the user, giving clear operational context, though it does not name a competing tool for starting new conversations.

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