makeInstantKokoroCall

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

With no annotations provided, the description carries the behavioral disclosure burden. It does a good job by revealing that the call is outbound, one-way, immediate, always Kokoro-voiced, and that it pre-generates and plays a clip. It does not mention billing, failure modes, or required permissions, but the core side effects are clearly stated.

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 two concise sentences with no filler. It front-loads the core action and immediate behavior, then adds the important pre-generation detail. Every part earns its place and it is easy for an agent to parse quickly.

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 side-effecting call tool with four well-documented parameters and no output schema, the description covers the essential selection and invocation context: directionality, timing, voice, endpoint, and pre-generation behavior. Minor gaps like return value, auth, and billing details remain, but they do not prevent an agent from understanding and invoking the tool 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?

The schema already documents all four parameters with descriptions, and coverage is 100%. The description reinforces the meaning of message ('pre-generates... clip') and voice ('always voiced by Kokoro TTS'), but it does not add substantial new parameter-level information beyond what the schema provides.

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 ('Place an immediate one-way outbound call') and names the exact endpoint. It clearly distinguishes this tool from siblings like makeInstantCall and quickCall by emphasizing that the call is always voiced by Kokoro TTS and pre-generates a per-recipient Kokoro clip.

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 when to use this tool—when you need an immediate, one-way Kokoro-voiced call—but it does not explicitly state when to choose it over alternatives or when not to use it. No sibling tools are named, leaving the selection logic somewhat implicit.

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