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

Annotations are absent, so the description must disclose behavioral traits. It only states the action without mentioning side effects, delivery guarantees, rate limits, or authentication requirements. The '[Buy]' prefix hints at a commercial aspect but is unexplained.

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 sentence and is efficient in length. However, the '[Buy]' prefix is cryptic and adds confusion without earning its place.

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 no annotations and no output schema, the description leaves out return behavior and side effects. For a mutation tool, it should at least note whether the send is synchronous, what happens on failure, or if there are costs. It is minimally adequate but not complete.

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?

With 0% schema description coverage, the description must explain the parameters. It does not explicitly describe 'body' or 'campaignId'; it only implies that a message is sent on a thread. The parameter names are self-explanatory, but the description adds no additional meaning beyond 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 uses the specific verb 'Send' and identifies the resource as 'a message on a campaign booking thread', which clearly distinguishes it from sibling tools like list_messages. It conveys the core action without ambiguity.

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 implies the tool is for messaging within a campaign booking thread, but it does not specify when to use it over alternatives, such as list_messages for reading. No exclusions or conditions are provided.

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