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

With no annotations provided, the description carries full responsibility. It discloses that the tool is asynchronous, non-obligatory, returns a secret unrecoverable token, requires bearer authentication, has daily and burst quotas, and an alarm for contacting many businesses. This is comprehensive behavioral information beyond what any structured annotation would provide.

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 primary action, followed by return values, token importance, and authentication details. It is structured logically and every sentence adds value. Could be trimmed slightly, but generally concise for the amount of information conveyed.

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?

The description covers the tool's purpose, return values, critical token behavior, authentication, rate limits, and related tools. It lacks explicit error handling beyond refusal naming the limit, but given the absence of output schema and annotations, it provides sufficient context for an AI agent to use the tool effectively.

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?

The input schema has 100% description coverage for all 6 parameters, so the schema already documents each parameter's meaning. The tool description does not add new parameter-level semantics beyond the schema; it only provides context about the slug coming from search_businesses and the importance of the token. 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?

The description clearly states the action ('Open a conversation with the person behind a listing'), specifies the asynchronous nature, and distinguishes from sibling tools by explaining that check_replies and send_followup are for reading replies and writing again. It also references search_businesses implicitly through the slug field.

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 guidelines by explaining the asynchronous model, emphasizing that the token is critical and must be saved, and detailing authentication requirements and rate limits. It contrasts with 'reading the knowledge base' to indicate when authentication is not needed, though it does not explicitly state when to use or not use this tool versus alternatives.

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