update_conversation_variables

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

With no annotations, the description carries the full burden of behavioral disclosure. It explains that variables are 'inherited by any subsequent voice/chat turn that renders the agent's prompt template' and details the 'replace' parameter's merge vs. replace behavior. This provides key behavioral transparency, though it could mention additional aspects like error handling or idempotency.

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 concise and well-structured. It opens with the core purpose, then provides a brief usage note, and includes an 'Args' list for parameter details. Every sentence earns its place, and the format is easy to scan.

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, usage, parameters, and behavioral nuances. Given that an output schema exists, the description need not explain return values. It does not address edge cases like invalid conversation IDs, but the provided context is sufficient for typical usage, leaving minor gaps.

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?

Despite the schema having 0% description coverage, the description's 'Args' section explains each parameter's purpose and behavior: conversation_id is the target thread, dynamic_variables is a dict of name/value pairs, and replace controls merge vs. replace semantics. This goes well beyond the schema types and defaults, adding significant meaning.

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 tool's function: 'Set or update dynamic_variables on a conversation thread.' It specifies the resource (conversation thread) and the action (set or update), which distinguishes it from sibling tools like send_conversation_message or get_conversation.

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 a clear usage context: 'Useful when context arrives out-of-band (CRM sync, webhook from your system, etc.).' This implies when to use the tool, but it does not explicitly state when not to use it or name alternative tools. Still, the guidance is useful and clear.

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